Merge pull request 'dev' (#68) from dev into main

Reviewed-on: #68

.placeholder/13-WASM_Modules/README.md

@@ -0,0 +1,3 @@
+https://github.com/istio-ecosystem/wasm-extensions
+
+https://github.com/istio-ecosystem/wasm-extensions/tree/master/extensions/basic_auth

.placeholder/text.md

@@ -1,11 +1,4 @@
 
-
-# Continues from
-
-- 01-hello_world_1_service_1_deployment
-
-
-
 https://istio.io/latest/docs/reference/config/networking/virtual-service/#HTTPRedirect
 
 ## The idea is that this rewrite is handled "externally" by the client, not by Istio.

00-Troubleshooting/README.md

@@ -3,6 +3,63 @@ gitea: none
 include_toc: true
 ---
 
+
+# Logs
+
+> **Note:**\
+> Remember that you can use the command `watch` or `watch -n 5` (where 5 refers every 5 seconds) in case of being interested on execute this commands periodically.
+
+## Istiod
+
+```shell
+kubectl logs -n istio-system -f deployments/istiod
+```
+
+## Istio-Proxy Pod
+
+This will display the logs from a deployment while targeting the `istio-proxy` container from the targeted pod/deployment.
+
+As well will attach the session to stream new logs. (`-f` `--follow`)
+
+```shell
+kubectl logs deployments/helloworld-default -f -c istio-proxy
+```
+
+```text
+[2023-05-15T00:42:03.699Z] "- - -" 0 UH - - "-" 0 0 0 - "-" "-" "-" "-" "-" BlackHoleCluster - 10.111.90.232:8080 172.17.121.65:52006 - -
+[2023-05-15T00:42:24.785Z] "HEAD / HTTP/1.1" 200 - via_upstream - "-" 0 0 2 1 "-" "curl/7.74.0" "c133cbf0-b57d-4fba-8f84-d683ab903399" "helloworld.default.svc.cluster.local" "172.17.121.65:80" inbound|80|| 127.0.0.6:51695 172.17.121.65:80 172.17.121.65:43786 outbound_.80_._.helloworld.default.svc.cluster.local default
+[2023-05-15T00:42:24.784Z] "HEAD / HTTP/1.1" 200 - via_upstream - "-" 0 0 5 4 "-" "curl/7.74.0" "c133cbf0-b57d-4fba-8f84-d683ab903399" "helloworld.default.svc.cluster.local" "172.17.121.65:80" outbound|80||helloworld.default.svc.cluster.local 172.17.121.65:43786 10.111.90.232:80 172.17.121.65:57030 - default
+[2023-05-15T00:43:23.209Z] "HEAD / HTTP/1.1" 200 - via_upstream - "-" 0 0 6 5 "-" "curl/7.74.0" "e1f0a2f3-93ff-4c41-8cb3-6d3a53fce065" "helloworld.foo.svc.cluster.local" "172.17.247.42:80" outbound|80||helloworld.foo.svc.cluster.local 172.17.121.65:55040 10.109.248.148:80 172.17.121.65:60520 - default
+[2023-05-15T00:43:29.751Z] "- - -" 0 UH - - "-" 0 0 0 - "-" "-" "-" "-" "-" BlackHoleCluster - 10.109.248.148:8080 172.17.121.65:40370 - -
+[2023-05-15T00:43:31.979Z] "- - -" 0 UH - - "-" 0 0 0 - "-" "-" "-" "-" "-" BlackHoleCluster - 10.109.248.148:8080 172.17.121.65:40402 - -
+```
+
+## Ingress
+
+The service targeted, `istio-ingressgateway`, is an Ingress Load Balancer service from Istio.
+
+```shell
+kubectl logs -n istio-system services/istio-ingressgateway
+```
+#### Invalid TLS context has neither subject CN nor SAN names
+
+The TLS certificate specified don't have the field CN or the field SAN.
+
+To address this issue, issue a new certificate that has at least one of those fields.
+
+#### initial fetch timed out for type.googleapis.com/envoy.extensions.transport_sockets.tls.v3.Secretthread
+
+This is due not being able to retrieve the TLS configuration assigned to the gateway.
+
+It's Important that the secret is located in the same namespace as the Istio Load Balancer used. In my case is the `istio-system`, but it will vary based on the environment.
+
+
+
+
+
+
+
+
 # Istioctl analyze
 
 `istioctl analyze` reviews the current configuration set.
@@ -52,50 +109,39 @@ Warning [IST0104] (Gateway default/helloworld-gateway) The gateway refers to a p
 
 Target a pod and start a packet capture on the istio-proxy container.
 
-This step requires istio to be installed with the flag `values.global.proxy.privileged=true`
+This step requires Istio to be installed with the flag `values.global.proxy.privileged=true`
 
 This is very useful to confirm if the service is receiving any traffic, or which is the traffic received.
 
 If mTLS is  enabled and configured, the traffic received should be encrypted.
 
 ```shell
-$ kubectl exec -n default  "$(kubectl get pod -n default -l app=helloworld -o jsonpath={.items..metadata.name})" -c istio-proxy -- sudo tcpdump dst port 80  -A
+kubectl exec -n default  "$(kubectl get pod -n default -l app=helloworld -o jsonpath={.items..metadata.name})" -c istio-proxy -- sudo tcpdump dst port 80  -A
+```
+```text
 tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
 listening on eth0, link-type EN10MB (Ethernet), snapshot length 262144 bytes
 ...
 ```
 
-# Logs
-
-> **Note:**\
-> Remember that you can use the command `watch` or `watch -n 5` (where 5 refers every 5 seconds) in case of being interested on execute this commands periodically.
-
-## Istiod
+# Istioctl proxy-status
+> **Note:** Shorthand is `ps`
 
 ```shell
-kubectl logs -n istio-system -f deployments/istiod
+istioctl ps
+```
+```text
+NAME                                                  CLUSTER        CDS        LDS        EDS        RDS          ECDS         ISTIOD                    VERSION
+helloworld-6798765f88-ql26n.default                   Kubernetes     SYNCED     SYNCED     SYNCED     SYNCED       NOT SENT     istiod-dbf5ff64-9kxxs     1.17.2
+helloworld2-dc9cb5db6-m47x7.default                   Kubernetes     SYNCED     SYNCED     SYNCED     SYNCED       NOT SENT     istiod-dbf5ff64-9kxxs     1.17.2
+istio-egressgateway-676bf68b54-d28fn.istio-system     Kubernetes     SYNCED     SYNCED     SYNCED     NOT SENT     NOT SENT     istiod-dbf5ff64-9kxxs     1.17.2
+istio-ingressgateway-8d56c999d-nv7ph.istio-system     Kubernetes     SYNCED     SYNCED     SYNCED     SYNCED       NOT SENT     istiod-dbf5ff64-9kxxs     1.17.2
 ```
 
-## Ingress
-
-The service targeted, `istio-ingressgateway`, is an Ingress Load Balancer service from Istio.
-
-```shell
-kubectl logs -n istio-system services/istio-ingressgateway
-```
-#### Invalid TLS context has neither subject CN nor SAN names
-
-The TLS certificate specified don't have the field CN or the field SAN.
-
-To address this issue, issue a new certificate that has at least one of those fields.
-
-#### initial fetch timed out for type.googleapis.com/envoy.extensions.transport_sockets.tls.v3.Secretthread 
-
-This is due not being able to retrieve the TLS configuration assigned to the gateway.
-
-It's Important that the secret is located in the same namespace as the Istio Load Balancer used. In my case is the `istio-system`, but it will vary based on the environment.
 
 # Istioctl proxy-config
+> **Note:** Shorthand is `pc`
+
 
 ## Check listeners
 
@@ -175,4 +221,8 @@ InboundPassthroughClusterIpv4                              -         -
 PassthroughCluster                                         -         -          -             ORIGINAL_DST     
 agent                                                      -         -          -             STATIC           
 ...
-```
+```
+
+# Other links
+
+## [Debugging with Istio](https://www.istioworkshop.io/12-debugging/01-istioctl-debug-command/)

01-Getting_Started/01-hello_world_1_service_1_deployment/Deployment.yaml

@@ -1,17 +1,3 @@
-apiVersion: v1
-kind: Service
-metadata:
-  name: helloworld
-  labels:
-    app: helloworld
-    service: helloworld
-spec:
-  ports:
-    - port: 80
-      name: http
-  selector:
-    app: helloworld
----
 apiVersion: apps/v1
 kind: Deployment
 metadata:

01-Getting_Started/01-hello_world_1_service_1_deployment/Gateway.yaml

@@ -0,0 +1,14 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"

01-Getting_Started/01-hello_world_1_service_1_deployment/README.md

@@ -0,0 +1,236 @@
+---
+gitea: none
+include_toc: true
+---
+
+
+# Description 
+
+This is the most basic example, most of the examples spread through this [repository](../../) will be using variants of this. 
+
+This example configures:
+
+    Generic Kubernetes resources:
+    - 1 Service
+    - 1 Deployment
+    
+    Istio resources:
+    - 1 Gateway
+    - 1 Virtual Service
+
+> **Note:**\
+> I don't intend to explain thing related to Kubernetes unless necessary.
+
+# Configuration
+
+## Service
+
+Creates a service named `helloworld`.
+
+This service listens for the port `80` expecting `HTTP` traffic and will forward the incoming traffic towards the port `80` from the destination pod.
+
+```yaml
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld
+```
+
+## Deployment
+
+Deploys a Nginx server that listens for the port `80`.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-nginx
+  labels:
+    app: helloworld
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+  template:
+    metadata:
+      labels:
+        app: helloworld
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent #Always
+          ports:
+            - containerPort: 80
+```
+
+## Gateway
+
+Deploys an Istio gateway that's listening to the port `80` for `HTTP` traffic.
+
+It doesn't filter for any specific host.
+
+The `selector` field is used to "choose" which Istio Load Balancers will have this gateway assigned to.
+
+The Istio `default` profile creates a Load Balancer in the namespace `istio-system` that has the label `istio: ingressgateway` set, allowing us to target that specific Load Balancer and assign this gateway resource to it.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"
+```
+
+## VirtualService
+
+The Virtual Service resources are used to route and filter the received traffic from the gateway resources, and route it towards the desired destination.
+
+On this example we select the gateway `helloworld-gateway`, which is the [gateway that 's described in the `Gateway` section](#gateway).
+
+On this resource, we are also not limiting the incoming traffic to any specific host, allowing for all the incoming traffic to go through the rules set. 
+
+Here we created a rule that will be applied on `HTTP` related traffic (including `HTTPS` and `HTTP2`) when the destination path is exactly `/helloworld`.
+
+This traffic will be forwarded to the port `80` of the destination service `helloworld` (the full path URL equivalent would be `helloworld.$NAMESPACE.svc.cluster.local`).
+
+Additionally, there will be an internal URL rewrite set, as if the URL is not modified, it would attempt to reach to the `/helloworld` path from the Nginx deployment, which currently has no content and would result in an error code `404` (Not found).
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld
+            port:
+              number: 80
+      rewrite:
+        uri: "/"
+```
+
+# Walkthrough
+
+## Deploy resources
+
+Deploy the resources.
+
+```shell
+kubectl apply -f ./ 
+```
+```text
+deployment.apps/helloworld-nginx created
+gateway.networking.istio.io/helloworld-gateway created
+service/helloworld created
+virtualservice.networking.istio.io/helloworld-vs created
+```
+
+## Wait for the deployment to be ready
+
+Wait for the Nginx deployment to be up and ready.
+
+```shell
+kubectl get deployment helloworld-nginx -w 
+```
+```text
+NAME               READY   UP-TO-DATE   AVAILABLE   AGE
+helloworld-nginx   1/1     1            1           44s
+```
+
+## Test the service
+
+### Get LB IP
+
+To perform the desired tests, we will need to obtain the IP Istio Load Balancer that we selected in the [Gateway section](#gateway).
+
+On my environment, the IP is the `192.168.1.50`.
+
+```shell
+kubectl get svc -l istio=ingressgateway -A
+```
+```text
+NAME                   TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)                                      AGE
+istio-ingressgateway   LoadBalancer   10.97.47.216   192.168.1.50   15021:31316/TCP,80:32012/TCP,443:32486/TCP   39h
+```
+
+### Curl /helloworld
+
+Due to accessing the path `/helloworld`, we are triggering the rule set on the [VirtualService configuration](#virtualservice), sending a request to the Nginx backend and returning us its contents. 
+
+```shell
+curl 192.168.1.50/helloworld -s | grep "<title>.*</title>" 
+```
+```text
+<title>Welcome to nginx!</title>
+```
+
+### Curl /other
+
+What happens if we access a path or URL that doesn't trigger any rule?
+
+
+```shell
+curl 192.168.1.50/other -s -I 
+```
+```text
+HTTP/1.1 404 Not Found
+date: Sun, 30 Apr 2023 22:16:30 GMT
+server: istio-envoy
+transfer-encoding: chunked
+```
+
+We receive a status code `404`.
+
+I would like to put emphasis on the following line returned:
+
+```text
+server: istio-envoy
+```
+
+This means that the contents returned was performed by the Istio service, therefore, the request was able to reach Istio and received a response from it.
+
+## Cleanup
+
+Finally, a cleanup from the resources deployed.
+
+```shell
+kubectl delete -f ./
+```
+```text
+deployment.apps "helloworld-nginx" deleted
+gateway.networking.istio.io "helloworld-gateway" deleted
+service "helloworld" deleted
+virtualservice.networking.istio.io "helloworld-vs" deleted
+```

01-Getting_Started/01-hello_world_1_service_1_deployment/Service.yaml

@@ -0,0 +1,13 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld

01-Getting_Started/01-hello_world_1_service_1_deployment/VirtualService.yaml

@@ -1,19 +1,4 @@
 apiVersion: networking.istio.io/v1alpha3
-kind: Gateway
-metadata:
-  name: helloworld-gateway
-spec:
-  selector:
-    istio: ingressgateway # use istio default controller
-  servers:
-    - port:
-        number: 80
-        name: http
-        protocol: HTTP
-      hosts:
-        - "*"
----
-apiVersion: networking.istio.io/v1alpha3
 kind: VirtualService
 metadata:
   name: helloworld-vs

01-Getting_Started/02-hello_world_1_service_2_deployments_unmanaged/Deployment.yaml

@@ -1,25 +1,3 @@
-# https://github.com/istio/istio/blob/master/samples/helloworld/helloworld.yaml
-apiVersion: v1
-kind: Service
-metadata:
-  name: helloworld
-  labels:
-    app: helloworld
-    service: helloworld
-spec:
-  ports:
-    - port: 80
-      name: http
-  selector:
-    app: helloworld
----
-#apiVersion: v1
-#kind: ServiceAccount
-#metadata:
-#  name: istio-helloworld
-#  labels:
-#    account:
----
 apiVersion: apps/v1
 kind: Deployment
 metadata:
@@ -36,7 +14,6 @@ spec:
       labels:
         app: helloworld
     spec:
-#      serviceAccountName: istio-helloworld
       containers:
         - name: helloworld
           image: nginx
@@ -63,7 +40,6 @@ spec:
       labels:
         app: helloworld
     spec:
-#      serviceAccountName: istio-helloworld
       containers:
         - name: helloworld
           image: httpd

01-Getting_Started/02-hello_world_1_service_2_deployments_unmanaged/Gateway.yaml

@@ -0,0 +1,14 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"

01-Getting_Started/02-hello_world_1_service_2_deployments_unmanaged/README.md

@@ -0,0 +1,306 @@
+---
+gitea: none
+include_toc: true
+---
+
+# Description
+
+This example deploys the same infrastructure as the  [previous example](../01-hello_world_1_service_1_deployment), this time containing 2 deployments under the same service.
+
+This example configures:
+
+    Generic Kubernetes resources:
+    - 1 Service
+    - 2 Deployments
+    
+    Istio resources:
+    - 1 Gateway
+    - 1 Virtual Service
+
+
+# Based on
+
+- [01-hello_world_1_service_1_deployment](../01-hello_world_1_service_1_deployment)
+
+# Configuration
+
+## Service
+
+Creates a service named `helloworld`.
+
+This service listens for the port `80` expecting `HTTP` traffic and will forward the incoming traffic towards the port `80` from the destination pod.
+
+```yaml
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld
+```
+
+## Deployment
+
+### helloworld-v1
+
+Deploys a Nginx server that listens for the port `80`.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-v1
+  labels:
+    app: helloworld
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+  template:
+    metadata:
+      labels:
+        app: helloworld
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent
+          ports:
+            - containerPort: 80
+```
+
+### helloworld-v2
+
+Deploys an Apache server that listens for the port `80`.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-v2
+  labels:
+    app: helloworld
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+  template:
+    metadata:
+      labels:
+        app: helloworld
+    spec:
+      containers:
+        - name: helloworld
+          image: httpd
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent
+          ports:
+            - containerPort: 80
+```
+
+## Gateway
+
+Deploys an Istio gateway that's listening to the port `80` for `HTTP` traffic.
+
+It doesn't filter for any specific host.
+
+The `selector` field is used to "choose" which Istio Load Balancers will have this gateway assigned to.
+
+The Istio `default` profile creates a Load Balancer in the namespace `istio-system` that has the label `istio: ingressgateway` set, allowing us to target that specific Load Balancer and assign this gateway resource to it.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"
+```
+
+## VirtualService
+
+The Virtual Service resources are used to route and filter the received traffic from the gateway resources, and route it towards the desired destination.
+
+On this example we select the gateway `helloworld-gateway`, which is the [gateway that 's described in the `Gateway` section](#gateway).
+
+On this resource, we are also not limiting the incoming traffic to any specific host, allowing for all the incoming traffic to go through the rules set.
+
+Here we created a rule that will be applied on `HTTP` related traffic (including `HTTPS` and `HTTP2`) when the destination path is exactly `/helloworld`.
+
+This traffic will be forwarded to the port `80` of the destination service `helloworld` (the full path URL equivalent would be `helloworld.$NAMESPACE.svc.cluster.local`).
+
+Additionally, there will be an internal URL rewrite set, as if the URL is not modified, it would attempt to reach to the `/helloworld` path from the Nginx deployment, which currently has no content and would result in an error code `404` (Not found).
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld
+            port:
+              number: 80
+      rewrite:
+        uri: "/"
+```
+
+
+# Walkthrough
+
+## Deploy resources
+
+Deploy the resources.
+
+```shell
+kubectl apply -f ./
+```
+```text 
+deployment.apps/helloworld-v1 created
+deployment.apps/helloworld-v2 created
+gateway.networking.istio.io/helloworld-gateway created
+service/helloworld created
+virtualservice.networking.istio.io/helloworld-vs created
+```
+
+## Wait for the pods to be ready
+
+Wait for the Apache and Nginx deployments to be up and ready.
+
+```shell
+kubectl get deployment helloworld-v{1..2} -w
+```
+```text 
+NAME            READY   UP-TO-DATE   AVAILABLE   AGE
+helloworld-v1   1/1     1            1           4m1s
+helloworld-v2   1/1     1            1           4m1s
+```
+
+## Test the service
+
+### Get LB IP
+
+To perform the desired tests, we will need to obtain the IP Istio Load Balancer that we selected in the [Gateway section](#gateway).
+
+On my environment, the IP is the `192.168.1.50`.
+
+```shell
+kubectl get svc -l istio=ingressgateway -A
+```
+```text
+NAME                   TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)                                      AGE
+istio-ingressgateway   LoadBalancer   10.97.47.216   192.168.1.50   15021:31316/TCP,80:32012/TCP,443:32486/TCP   39h
+```
+
+### Curl
+
+Performing a series of `curl` requests, we can observe how the response iterate between the Nginx and Apache backends. 
+
+```shell
+curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+```
+```text
+<h1>Welcome to nginx!</h1>
+```
+
+```shell
+curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+```
+```text
+<html><body><h1>It works!</h1></body></html>
+```
+
+```shell
+curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+```
+```text
+<h1>Welcome to nginx!</h1>
+```
+
+```shell
+curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+```
+```text
+<html><body><h1>It works!</h1></body></html>
+```
+
+```shell
+curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+```
+```text
+<h1>Welcome to nginx!</h1>
+```
+
+```shell
+curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+```
+```text
+<html><body><h1>It works!</h1></body></html>
+```
+
+```shell
+curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+```
+```text
+<h1>Welcome to nginx!</h1>
+```
+
+```shell
+curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+```
+```text
+<h1>Welcome to nginx!</h1>
+```
+
+```shell
+curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>"
+```
+```text
+<html><body><h1>It works!</h1></body></html>
+```
+
+## Cleanup
+
+Finally, a cleanup from the resources deployed.
+
+```shell
+kubectl delete -f ./
+```
+```text
+deployment.apps "helloworld-v1" deleted
+deployment.apps "helloworld-v2" deleted
+gateway.networking.istio.io "helloworld-gateway" deleted
+service "helloworld" deleted
+virtualservice.networking.istio.io "helloworld-vs" deleted
+```

01-Getting_Started/02-hello_world_1_service_2_deployments_unmanaged/Service.yaml

@@ -0,0 +1,13 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld

01-Getting_Started/02-hello_world_1_service_2_deployments_unmanaged/VirtualService.yaml

@@ -1,22 +1,4 @@
 apiVersion: networking.istio.io/v1alpha3
-kind: Gateway
-metadata:
-  name: helloworld-gateway
-spec:
-  selector:
-    istio: ingressgateway
-  servers:
-    - port:
-        number: 443
-        name: secure-http
-        protocol: HTTPS
-      hosts:
-        - "*"
-      tls:
-        mode: SIMPLE
-        credentialName: my-tls-cert-secret
----
-apiVersion: networking.istio.io/v1alpha3
 kind: VirtualService
 metadata:
   name: helloworld-vs

01-Getting_Started/03-hello_world_1_service_2_deployments_managed_version/Deployment.yaml

@@ -1,37 +1,11 @@
-# https://github.com/istio/istio/blob/master/samples/helloworld/helloworld.yaml
-
----
-apiVersion: v1
-kind: Service
-metadata:
-  name: helloworld
-  namespace: defaultnt
-  labels:
-    app: helloworldll
-    service: helloworld
-    sidecar.istio.io/inject: "false"
-spec:
-  ports:
-    - port: 80
-      name: http
-  selector:
-    app: helloworld
----
-#apiVersion: v1
-#kind: ServiceAccount
-#metadata:
-#  name: istio-helloworld
-#  labels:
-#    account:
----
 apiVersion: apps/v1
 kind: Deployment
 metadata:
   name: helloworld-v1
-  namespace: defaultnt
   labels:
     app: helloworld
     version: v1
+  namespace: default
 spec:
   replicas: 1
   selector:
@@ -58,10 +32,10 @@ apiVersion: apps/v1
 kind: Deployment
 metadata:
   name: helloworld-v2
-  namespace: defaultnt
   labels:
     app: helloworld
     version: v2
+  namespace: default
 spec:
   replicas: 1
   selector:
@@ -82,5 +56,4 @@ spec:
               cpu: "100m"
           imagePullPolicy: IfNotPresent
           ports:
-            - containerPort: 80
----
+            - containerPort: 80

01-Getting_Started/03-hello_world_1_service_2_deployments_managed_version/DestinationRule.yaml

@@ -0,0 +1,16 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: DestinationRule
+metadata:
+  # name: helloworld (OLD)
+  name: helloworld.default.svc.cluster.local # Destination that will "interject"
+  namespace: default
+spec:
+  #  host: helloworld # destination service (OLD)
+  host: helloworld.default.svc.cluster.local # Full destination service, lil better for consistency
+  subsets:
+    - name: v1
+      labels:
+        version: v1
+    - name: v2
+      labels:
+        version: v2

01-Getting_Started/03-hello_world_1_service_2_deployments_managed_version/Gateway.yaml

@@ -0,0 +1,15 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+  namespace: default
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"

01-Getting_Started/03-hello_world_1_service_2_deployments_managed_version/README.md

@@ -0,0 +1,426 @@
+---
+gitea: none
+include_toc: true
+---
+
+# Description
+
+Based on the [previous example](../02-hello_world_1_service_2_deployments_unmanaged), where we created 2 deployments under the same service, we will attribute different tags to each Deployment, and afterwards, through the usage of a [DestinationRule](#destinationrule), internationally target the desired backend to route the traffic towards it. 
+
+This is example is based on the following post regarding [canary deployments on Istio](https://istio.io/latest/blog/2017/0.1-canary/).
+
+This example configures:
+
+    Generic Kubernetes resources:
+    - 1 Service
+    - 2 Deployments
+    
+    Istio resources:
+    - 1 Gateway
+    - 1 Virtual Service
+    - 1 Destination rule
+
+Additionally, for consistency, now the resources are being created in the `default` namespace.
+
+As well, on the [VirtualService section](#virtualservice), we are targeting the service `helloworld` by the full URL, where on previous examples it was targeted by `helloworld`, now it's targeted by `helloworld.default.svc.cluster.local`.
+
+# Based on
+
+- [02-hello_world_1_service_2_deployments_unmanaged](../02-hello_world_1_service_2_deployments_unmanaged)
+
+# Configuration
+
+## Service
+
+Creates a service named `helloworld`.
+
+This service listens for the port `80` expecting `HTTP` traffic and will forward the incoming traffic towards the port `80` from the destination pod.
+
+```yaml
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld
+```
+
+## Deployment
+
+### helloworld-v1
+
+Deploys a Nginx server that listens for the port `80`.
+
+On this deployment, we attributed the label `version` set to `v1`, this will be used by the [DestinationRule](#destinationrule) resource to target this deployment.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-v1
+  labels:
+    app: helloworld
+    version: v1
+  namespace: default
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+      version: v1
+  template:
+    metadata:
+      labels:
+        app: helloworld
+        version: v1
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent
+          ports:
+            - containerPort: 80
+```
+
+### helloworld-v2
+
+Deploys an Apache server that listens for the port `80`.
+
+On this deployment, we attributed the label `version` set to `v2`, this will be used by the [DestinationRule](#destinationrule) resource to target this deployment.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-v2
+  labels:
+    app: helloworld
+    version: v2
+  namespace: default
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+      version: v2
+  template:
+    metadata:
+      labels:
+        app: helloworld
+        version: v2
+    spec:
+      containers:
+        - name: helloworld
+          image: httpd
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent
+          ports:
+            - containerPort: 80
+```
+
+## Gateway
+
+Deploys an Istio gateway that's listening to the port `80` for `HTTP` traffic.
+
+It doesn't filter for any specific host.
+
+The `selector` field is used to "choose" which Istio Load Balancers will have this gateway assigned to.
+
+The Istio `default` profile creates a Load Balancer in the namespace `istio-system` that has the label `istio: ingressgateway` set, allowing us to target that specific Load Balancer and assign this gateway resource to it.
+
+
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+  namespace: default
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"
+```
+
+## VirtualService
+
+The Virtual Service resources are used to route and filter the received traffic from the gateway resources, and route it towards the desired destination.
+
+On this example we select the gateway `helloworld-gateway`, which is the [gateway that 's described in the `Gateway` section](#gateway).
+
+On this resource, we are also not limiting the incoming traffic to any specific host, allowing for all the incoming traffic to go through the rules set.
+
+Here we created a rule that will be applied on `HTTP` related traffic (including `HTTPS` and `HTTP2`) when the destination path is exactly `/helloworld`.
+
+This traffic will be forwarded to the port `80` of the destination service `helloworld` (the full path URL equivalent would be `helloworld.$NAMESPACE.svc.cluster.local`).
+
+There will be an internal URL rewrite set, as if the URL is not modified, it would attempt to reach to the `/helloworld` path from the Nginx deployment, which currently has no content and would result in an error code `404` (Not found).
+
+Also, there's been configured 2 destinations under the same rule, each one with a `subset` set, which will be used by the [DestinationRule](#destinationrule) object to manage the traffic from each destination.
+
+As well, where each one of the destinations mentioned, has a `weight` set, this value will be used to distribute the incoming requests towards the specified subsets.
+
+> **Note:**
+> A 20% of the traffic will be sent to the `subset` v1, meanwhile 80% will be sent to the `subset` v2.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+  namespace: default
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld.default.svc.cluster.local
+            #            host: helloworld (OLD)
+            port:
+              number: 80
+            subset: v1
+          weight: 20
+        - destination:
+            #            host: helloworld (OLD)
+            host: helloworld.default.svc.cluster.local
+            port:
+              number: 80
+            subset: v2
+          weight: 80
+      rewrite:
+        uri: "/"
+```
+
+## DestinationRule
+
+This `DestinationRule` interferes with the traffic with destination `helloworld.default.svc.cluster.local`.
+
+Contains 2 subsets defined, where each one will target a different backend.
+
+A reminder that the `version: v1` was given to the Nginx backend, meanwhile the Apache backend had set `version: v2`.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: DestinationRule
+metadata:
+  # name: helloworld (OLD)
+  name: helloworld.default.svc.cluster.local # Destination that will "interject"
+  namespace: default
+spec:
+  #  host: helloworld # destination service (OLD)
+  host: helloworld.default.svc.cluster.local # Full destination service, lil better for consistency
+  subsets:
+    - name: v1
+      labels:
+        version: v1
+    - name: v2
+      labels:
+        version: v2
+```
+
+# Walkthrough
+
+## Deploy resources
+
+Deploy the resources.
+
+```shell
+kubectl apply -f ./
+```
+```text 
+deployment.apps/helloworld-v1 created
+deployment.apps/helloworld-v2 created
+destinationrule.networking.istio.io/helloworld.default.svc.cluster.local created
+gateway.networking.istio.io/helloworld-gateway created
+service/helloworld created
+virtualservice.networking.istio.io/helloworld-vs created
+```
+
+## Wait for the pods to be ready
+
+Wait for the Apache and Nginx deployments to be up and ready.
+
+```shell
+watch -n 2 kubectl get deployment helloworld-v{1..2} 
+```
+```text 
+NAME            READY   UP-TO-DATE   AVAILABLE   AGE
+helloworld-v1   1/1     1            1           58s
+helloworld-v2   1/1     1            1           58s
+```
+
+## Test the service
+
+### Get LB IP
+
+To perform the desired tests, we will need to obtain the IP Istio Load Balancer that we selected in the [Gateway section](#gateway).
+
+On my environment, the IP is the `192.168.1.50`.
+
+```shell
+kubectl get svc -l istio=ingressgateway -A
+```
+```text
+NAME                   TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)                                      AGE
+istio-ingressgateway   LoadBalancer   10.97.47.216   192.168.1.50   15021:31316/TCP,80:32012/TCP,443:32486/TCP   39h
+```
+
+### Curl
+
+By performing a series of curls, we can notice how the output received iterates between Nginx and Apache.
+
+If we take into account the configuration set, and we review the results, we can notice how the ratio is close to the one configured in the [VirtualService](#virtualservice) section.
+
+> Nginx instances (v1): 2 \
+> Apache instances (v2): 9
+
+```text
+$ curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>"
+<html><body><h1>It works!</h1></body></html>
+
+$ curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+<html><body><h1>It works!</h1></body></html>
+
+$ curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+<html><body><h1>It works!</h1></body></html>
+
+$ curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+<html><body><h1>It works!</h1></body></html>
+
+$ curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+<html><body><h1>It works!</h1></body></html>
+
+$ curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+<html><body><h1>It works!</h1></body></html>
+
+$ curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+<html><body><h1>It works!</h1></body></html>
+
+$ curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+<html><body><h1>It works!</h1></body></html>
+
+$ curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+<h1>Welcome to nginx!</h1>
+
+$ curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+<html><body><h1>It works!</h1></body></html>
+
+$ curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>"
+<h1>Welcome to nginx!</h1>
+```
+
+## Check Istio internal configurations created
+
+Using the command `istioctl x describe pod $POD`, we can see which Istio configuration is currently attributed to that specific pod.
+
+### v1
+
+We can notice the following line:
+
+`Weight 20%`
+
+Which matches the configuration set in the [VirtualService](#virtualservice) configuration.
+
+```sh
+istioctl x describe pod $(kubectl get pod -l app=helloworld,version=v1 -o jsonpath='{.items[0].metadata.name}')
+```
+```text
+Pod: helloworld-v1-7454b56b86-4cksf
+   Pod Revision: default
+   Pod Ports: 80 (helloworld), 15090 (istio-proxy)
+--------------------
+Service: helloworld
+   Port: http 80/HTTP targets pod port 80
+DestinationRule: helloworld for "helloworld.default.svc.cluster.local"
+   Matching subsets: v1
+      (Non-matching subsets v2)
+   No Traffic Policy
+--------------------
+Effective PeerAuthentication:
+   Workload mTLS mode: PERMISSIVE
+
+
+Exposed on Ingress Gateway http://192.168.1.50
+VirtualService: helloworld-vs
+   Weight 20%
+   /helloworld
+```
+
+### v2
+
+We can notice the following line:
+
+`Weight 80%`
+
+Which matches the configuration set in the [VirtualService](#virtualservice) configuration.
+
+```shell
+istioctl x describe pod `kubectl get pod -l app=helloworld,version=v2 -o jsonpath='{.items[0].metadata.name 
+```
+```text
+Pod: helloworld-v2-64b5656d99-5bwgr
+   Pod Revision: default
+   Pod Ports: 80 (helloworld), 15090 (istio-proxy)
+--------------------
+Service: helloworld
+   Port: http 80/HTTP targets pod port 80
+DestinationRule: helloworld for "helloworld.default.svc.cluster.local"
+   Matching subsets: v2
+      (Non-matching subsets v1)
+   No Traffic Policy
+--------------------
+Effective PeerAuthentication:
+   Workload mTLS mode: PERMISSIVE
+
+
+Exposed on Ingress Gateway http://192.168.1.50
+VirtualService: helloworld-vs
+   Weight 80%
+   /helloworld
+```
+
+## Cleanup
+
+Finally, a cleanup from the resources deployed.
+
+```shell
+kubectl delete -f ./
+```
+```text
+deployment.apps "helloworld-v1" deleted
+deployment.apps "helloworld-v2" deleted
+destinationrule.networking.istio.io "helloworld.default.svc.cluster.local" deleted
+gateway.networking.istio.io "helloworld-gateway" deleted
+service "helloworld" deleted
+virtualservice.networking.istio.io "helloworld-vs" deleted
+```
+
+
+# Links of Interest
+
+- https://istio.io/latest/blog/2017/0.1-canary/
+- https://istio.io/latest/docs/reference/config/networking/destination-rule/#DestinationRule

01-Getting_Started/03-hello_world_1_service_2_deployments_managed_version/Service.yaml

@@ -0,0 +1,14 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+  namespace: default
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld

01-Getting_Started/03-hello_world_1_service_2_deployments_managed_version/VirtualService.yaml

@@ -1,23 +1,8 @@
-# https://github.com/istio/istio/blob/master/samples/helloworld/helloworld-gateway.yaml
-apiVersion: networking.istio.io/v1alpha3
-kind: Gateway
-metadata:
-  name: helloworld-gateway
-spec:
-  selector:
-    istio: ingressgateway # use istio default controller
-  servers:
-    - port:
-        number: 80
-        name: http
-        protocol: HTTP
-      hosts:
-        - "*"
----
 apiVersion: networking.istio.io/v1alpha3
 kind: VirtualService
 metadata:
   name: helloworld-vs
+  namespace: default
 spec:
   hosts:
     - "*"
@@ -30,7 +15,17 @@ spec:
       route:
         - destination:
             host: helloworld.default.svc.cluster.local
+            #            host: helloworld (OLD)
             port:
               number: 80
+            subset: v1
+          weight: 80
+        - destination:
+            #            host: helloworld (OLD)
+            host: helloworld.default.svc.cluster.local
+            port:
+              number: 80
+            subset: v2
+          weight: 20
       rewrite:
         uri: "/"

01-Getting_Started/04-hello_world_1_service_2_deployments_managed_version_foo_namespace/01-namespace.yaml

@@ -0,0 +1,4 @@
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: foo

01-Getting_Started/04-hello_world_1_service_2_deployments_managed_version_foo_namespace/Deployment.yaml

@@ -1,29 +1,8 @@
-# https://github.com/istio/istio/blob/master/samples/helloworld/helloworld.yaml
-apiVersion: v1
-kind: Service
-metadata:
-  name: helloworld
-  labels:
-    app: helloworld
-    service: helloworld
-spec:
-  ports:
-    - port: 80
-      name: http
-  selector:
-    app: helloworld
----
-#apiVersion: v1
-#kind: ServiceAccount
-#metadata:
-#  name: istio-helloworld
-#  labels:
-#    account:
----
 apiVersion: apps/v1
 kind: Deployment
 metadata:
   name: helloworld-v1
+  namespace: foo
   labels:
     app: helloworld
     version: v1
@@ -39,7 +18,6 @@ spec:
         app: helloworld
         version: v1
     spec:
-#      serviceAccountName: istio-helloworld
       containers:
         - name: helloworld
           image: nginx
@@ -54,6 +32,7 @@ apiVersion: apps/v1
 kind: Deployment
 metadata:
   name: helloworld-v2
+  namespace: foo
   labels:
     app: helloworld
     version: v2
@@ -69,7 +48,6 @@ spec:
         app: helloworld
         version: v2
     spec:
-#      serviceAccountName: istio-helloworld
       containers:
         - name: helloworld
           image: httpd

01-Getting_Started/04-hello_world_1_service_2_deployments_managed_version_foo_namespace/DestinationRule.yaml

@@ -0,0 +1,14 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: DestinationRule
+metadata:
+  name: helloworld
+  namespace: foo
+spec:
+  host: helloworld.foo.svc.cluster.local # Full destination service, lil better for consistency
+  subsets:
+    - name: v1
+      labels:
+        version: v1
+    - name: v2
+      labels:
+        version: v2

01-Getting_Started/04-hello_world_1_service_2_deployments_managed_version_foo_namespace/Gateway.yaml

@@ -0,0 +1,15 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+  namespace: default
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"

01-Getting_Started/04-hello_world_1_service_2_deployments_managed_version_foo_namespace/README.md

@@ -0,0 +1,374 @@
+---
+gitea: none
+include_toc: true
+---
+
+# Description
+
+Based on the [previous example](../03-hello_world_1_service_2_deployments_managed_version), we create the previous deployments in a different namespace than the Istio VirtualService object, in this case we create them in the namespace `foo`.
+
+This is example is based on the following post regarding [canary deployments on Istio](https://istio.io/latest/blog/2017/0.1-canary/).
+
+This example configures:
+
+    Generic Kubernetes resources:
+    - 1 Namespace
+    - 1 Service
+    - 2 Deployments
+    
+    Istio resources:
+    - 1 Gateway
+    - 1 Virtual Service
+    - 1 Destination rule
+
+Additionally, for consistency, now the resources are being created in the `default` namespace.
+
+On this example, the `service`, the `deployment`, and the Istio `DestinationRule` are being created in the namespace `foo`.
+
+As well, on the [VirtualService section](#virtualservice), we are targeting the service `helloworld` by the full URL, where on previous examples it was targeted by `helloworld`, now it's targeted by `helloworld.default.svc.cluster.local`.
+
+# Based on
+
+- [03-hello_world_1_service_2_deployments_managed_version](../03-hello_world_1_service_2_deployments_managed_version)
+
+# Configuration
+
+## Namespace
+
+Creates a namespace named `foo`.
+
+```yaml
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: foo
+```
+
+## Service
+
+Creates a service named `helloworld`.
+
+This service listens for the port `80` expecting `HTTP` traffic and will forward the incoming traffic towards the port `80` from the destination pod.
+
+The service is created in the namespace `foo`.
+
+```yaml
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  namespace: foo
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld
+```
+
+## Deployment
+
+### helloworld-v1
+
+Deploys a Nginx server that listens for the port `80`.
+
+On this deployment, we attributed the label `version` set to `v1`, this will be used by the [DestinationRule](#destinationrule) resource to target this deployment.
+
+The deployment is created in the namespace `foo`.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-v1
+  namespace: foo
+  labels:
+    app: helloworld
+    version: v1
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+      version: v1
+  template:
+    metadata:
+      labels:
+        app: helloworld
+        version: v1
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent
+          ports:
+            - containerPort: 80
+```
+
+### helloworld-v2
+
+Deploys an Apache server that listens for the port `80`.
+
+On this deployment, we attributed the label `version` set to `v2`, this will be used by the [DestinationRule](#destinationrule) resource to target this deployment.
+
+The deployment is created in the namespace `foo`.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-v2
+  namespace: foo
+  labels:
+    app: helloworld
+    version: v2
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+      version: v2
+  template:
+    metadata:
+      labels:
+        app: helloworld
+        version: v2
+    spec:
+      containers:
+        - name: helloworld
+          image: httpd
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent
+          ports:
+            - containerPort: 80
+```
+
+## Gateway
+
+Deploys an Istio gateway that's listening to the port `80` for `HTTP` traffic.
+
+It doesn't filter for any specific host.
+
+The `selector` field is used to "choose" which Istio Load Balancers will have this gateway assigned to.
+
+The Istio `default` profile creates a Load Balancer in the namespace `istio-system` that has the label `istio: ingressgateway` set, allowing us to target that specific Load Balancer and assign this gateway resource to it.
+
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+  namespace: default
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"
+```
+
+## VirtualService
+
+The Virtual Service resources are used to route and filter the received traffic from the gateway resources, and route it towards the desired destination.
+
+On this example we select the gateway `helloworld-gateway`, which is the [gateway that 's described in the `Gateway` section](#gateway).
+
+On this resource, we are also not limiting the incoming traffic to any specific host, allowing for all the incoming traffic to go through the rules set.
+
+Here we created a rule that will be applied on `HTTP` related traffic (including `HTTPS` and `HTTP2`) when the destination path is exactly `/helloworld`.
+
+This traffic will be forwarded to the port `80` of the destination service `helloworld` located in the namespace `foo`.
+
+There will be an internal URL rewrite set, as if the URL is not modified, it would attempt to reach to the `/helloworld` path from the Nginx deployment, which currently has no content and would result in an error code `404` (Not found).
+
+Also, there's been configured 2 destinations under the same rule, each one with a `subset` set, which will be used by the [DestinationRule](#destinationrule) object to manage the traffic from each destination.
+
+As well, where each one of the destinations mentioned, has a `weight` set, this value will be used to distribute the incoming requests towards the specified subsets.
+
+> **Note:**
+> A 20% of the traffic will be sent to the `subset` v1, meanwhile 80% will be sent to the `subset` v2.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+  namespace: default
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld.foo.svc.cluster.local
+            port:
+              number: 80
+            subset: v1
+          weight: 20
+        - destination:
+            host: helloworld.foo.svc.cluster.local
+            port:
+              number: 80
+            subset: v2
+          weight: 80
+      rewrite:
+        uri: "/"
+```
+## DestinationRule
+
+This `DestinationRule` interferes with the traffic with destination `helloworld.foo.svc.cluster.local`.
+
+Contains 2 subsets defined, where each one will target a different backend.
+
+A reminder that the `version: v1` was given to the Nginx backend, meanwhile the Apache backend had set `version: v2`.
+
+This resource is created in the namespace `foo`.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: DestinationRule
+metadata:
+  name: helloworld
+  namespace: foo
+spec:
+  host: helloworld.foo.svc.cluster.local # Full destination service, lil better for consistency
+  subsets:
+    - name: v1
+      labels:
+        version: v1
+    - name: v2
+      labels:
+        version: v2
+```
+
+
+## Deploy resources
+
+Deploy the resources.
+
+```shell
+kubectl apply -f ./
+```
+```text 
+deployment.apps/helloworld-v1 created
+deployment.apps/helloworld-v2 created
+destinationrule.networking.istio.io/helloworld.default.svc.cluster.local created
+gateway.networking.istio.io/helloworld-gateway created
+service/helloworld created
+virtualservice.networking.istio.io/helloworld-vs created
+```
+
+## Wait for the pods to be ready
+
+Wait for the Apache and Nginx deployments to be up and ready.
+
+```shell
+watch -n 2 kubectl get deployment helloworld-v{1..2} 
+```
+```text 
+NAME            READY   UP-TO-DATE   AVAILABLE   AGE
+helloworld-v1   1/1     1            1           58s
+helloworld-v2   1/1     1            1           58s
+```
+
+## Test the service
+
+### Get LB IP
+
+To perform the desired tests, we will need to obtain the IP Istio Load Balancer that we selected in the [Gateway section](#gateway).
+
+On my environment, the IP is the `192.168.1.50`.
+
+```shell
+kubectl get svc -l istio=ingressgateway -A
+```
+```text
+NAME                   TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)                                      AGE
+istio-ingressgateway   LoadBalancer   10.97.47.216   192.168.1.50   15021:31316/TCP,80:32012/TCP,443:32486/TCP   39h
+```
+
+### Curl
+
+As we can see, we can reach out to the service, now located in the namespace `foo`.
+
+As well, if we check the ration on which we reached the backends, we can still see how the [VirtualService](#virtualservice) weight configured to the subsets is still being applied.
+
+> Nginx: 3\
+> Apache: 9
+
+```text
+curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+<html><body><h1>It works!</h1></body></html>
+
+$ 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+<html><body><h1>It works!</h1></body></html>
+
+$ 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+<html><body><h1>It works!</h1></body></html>
+
+$ 192.168.1.50/helloworld -s | grep "<h1>.*</h1>"
+<html><body><h1>It works!</h1></body></html>
+
+$ 192.168.1.50/helloworld -s | grep "<h1>.*</h1>"
+<h1>Welcome to nginx!</h1>
+
+$ 192.168.1.50/helloworld -s | grep "<h1>.*</h1>"
+<html><body><h1>It works!</h1></body></html>
+
+$ 192.168.1.50/helloworld -s | grep "<h1>.*</h1>"
+<html><body><h1>It works!</h1></body></html>
+
+$ 192.168.1.50/helloworld -s | grep "<h1>.*</h1>"
+<h1>Welcome to nginx!</h1>
+
+$ 192.168.1.50/helloworld -s | grep "<h1>.*</h1>"
+<html><body><h1>It works!</h1></body></html>
+
+$ 192.168.1.50/helloworld -s | grep "<h1>.*</h1>"
+<html><body><h1>It works!</h1></body></html>
+
+$ 192.168.1.50/helloworld -s | grep "<h1>.*</h1>"
+<h1>Welcome to nginx!</h1>
+
+$ 192.168.1.50/helloworld -s | grep "<h1>.*</h1>"
+<html><body><h1>It works!</h1></body></html>
+
+$ 192.168.1.50/helloworld -s | grep "<h1>.*</h1>"
+<html><body><h1>It works!</h1></body></html>
+```
+
+
+## Cleanup
+
+Finally, a cleanup from the resources deployed.
+
+```shell
+kubectl delete -f ./
+```
+```text
+namespace "foo" deleted
+deployment.apps "helloworld-v1" deleted
+deployment.apps "helloworld-v2" deleted
+destinationrule.networking.istio.io "helloworld" deleted
+gateway.networking.istio.io "helloworld-gateway" deleted
+service "helloworld" deleted
+virtualservice.networking.istio.io "helloworld-vs" deleted
+```

01-Getting_Started/04-hello_world_1_service_2_deployments_managed_version_foo_namespace/Service.yaml

@@ -0,0 +1,14 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  namespace: foo
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld

01-Getting_Started/04-hello_world_1_service_2_deployments_managed_version_foo_namespace/VirtualService.yaml

@@ -0,0 +1,29 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+  namespace: default
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld.foo.svc.cluster.local
+            port:
+              number: 80
+            subset: v1
+          weight: 20
+        - destination:
+            host: helloworld.foo.svc.cluster.local
+            port:
+              number: 80
+            subset: v2
+          weight: 80
+      rewrite:
+        uri: "/"

01-Getting_Started/README.md

@@ -0,0 +1,51 @@
+---
+gitea: none
+include_toc: true
+---
+
+# Getting Started
+
+The idea of these examples is to get yourself familiarized with the basic elements used on Istio, allowing you to
+explore the documentation as well of proceeding with other examples or tests on your onw.
+
+On these examples you will find the following Istio resources:
+
+- Gateway
+- VirtualService
+- DestinationRule
+
+# Examples
+
+- 01-hello_world_1_service_1_deployment
+
+- 02-hello_world_1_service_2_deployments_unmanaged
+
+- 03-hello_world_1_service_2_deployments_managed_version
+
+- 04-hello_world_1_service_2_deployments_managed_version_foo_namespace
+
+## Requirements:
+
+- A Kubernetes cluster (with a CNI network plugin, on my environment I have used [Calico](https://docs.tigera.io/calico/))
+
+- Istio installed
+
+# How to get started?
+
+## Install Istio
+
+Follow [this](https://istio.io/latest/docs/setup/getting-started/) guide to install the `default` profile.
+
+Specifically, the steps of [Download Istio](https://istio.io/latest/docs/setup/getting-started/#download) and [Install Istio](https://istio.io/latest/docs/setup/getting-started/#install). 
+
+Once this is set, proceed with the rest of the installation.
+
+## Setting up a Cluster?
+
+Consider using this.
+
+It's what I used to set up my labs for testing (which is the environment that I to do this repository/set of examples).
+
+https://gitea.filterhome.xyz/ofilter/ansible_kubernetes_cluster
+
+Also, I have added MetalLB to allow for my Load Balancers to get a Local IP and be available through the local network environment.

02-Traffic_management/01-header_routing/Deployment.yaml

@@ -1,18 +1,3 @@
-# https://github.com/istio/istio/blob/master/samples/helloworld/helloworld.yaml
-apiVersion: v1
-kind: Service
-metadata:
-  name: helloworld
-  labels:
-    app: helloworld
-    service: helloworld
-spec:
-  ports:
-    - port: 80
-      name: http
-  selector:
-    app: helloworld
----
 apiVersion: apps/v1
 kind: Deployment
 metadata:

02-Traffic_management/01-header_routing/DestinationRoute.yaml

@@ -0,0 +1,16 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: DestinationRule
+metadata:
+  name: helloworld.default.svc.cluster.local # Destination that will "interject"
+spec:
+  host: helloworld.default.svc.cluster.local # Full destination service, lil better for consistency
+  subsets:
+    - name: default
+      labels:
+        version: v0
+    - name: nginx
+      labels:
+        version: v1
+    - name: apache
+      labels:
+        version: v2

02-Traffic_management/01-header_routing/Gateway.yaml

@@ -0,0 +1,14 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"

02-Traffic_management/01-header_routing/README.md

@@ -0,0 +1,456 @@
+---
+gitea: none
+include_toc: true
+---
+
+# Description
+
+The [previous example](../../01-Getting_Started/03-hello_world_1_service_2_deployments_managed_version), we use the values set in the headers from the `HTTP` request received to route the traffic to different backends.
+
+Additionally, we configure a default rule where the unmatched traffic will go.
+
+This example configures:
+
+    Generic Kubernetes resources:
+    - 1 Namespace
+    - 1 Service
+    - 3 Deployments
+    
+    Istio resources:
+    - 1 Gateway
+    - 1 Virtual Service
+    - 1 Destination rule
+
+# Based on
+
+- [03-hello_world_1_service_2_deployments_managed_version](../../01-Getting_Started/03-hello_world_1_service_2_deployments_managed_version)
+
+# Configuration
+
+## Service
+
+Creates a service named `helloworld`.
+
+This service listens for the port `80` expecting `HTTP` traffic and will forward the incoming traffic towards the port `80` from the destination pod.
+
+```yaml
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld
+```
+
+## Deployment
+
+We will create 3 different deployments where the traffic will be distributed, targeting the labels set to the pods.
+
+Deployments created:
+
+- helloworld-v0
+- helloworld-v1
+- helloworld-v2
+
+### helloworld-v0
+
+Deploys a Whoami server that listens for the port `80`.
+
+On this deployment, we attributed the label `version` set to `v0`, this will be used by the [DestinationRule](#destinationrule) resource to target this deployment.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-v0
+  labels:
+    app: helloworld
+    version: v0
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+      version: v0
+  template:
+    metadata:
+      labels:
+        app: helloworld
+        version: v0
+    spec:
+      containers:
+        - name: helloworld
+          image: containous/whoami
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent
+          ports:
+            - containerPort: 80
+```
+
+### helloworld-v1
+
+Deploys a Nginx server that listens for the port `80`.
+
+On this deployment, we attributed the label `version` set to `v1`, this will be used by the [DestinationRule](#destinationrule) resource to target this deployment.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-v1
+  labels:
+    app: helloworld
+    version: v1
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+      version: v1
+  template:
+    metadata:
+      labels:
+        app: helloworld
+        version: v1
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent
+          ports:
+            - containerPort: 80
+```
+
+
+### helloworld-v2
+
+Deploys an Apache server that listens for the port `80`.
+
+On this deployment, we attributed the label `version` set to `v2`, this will be used by the [DestinationRule](#destinationrule) resource to target this deployment.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-v2
+  labels:
+    app: helloworld
+    version: v2
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+      version: v2
+  template:
+    metadata:
+      labels:
+        app: helloworld
+        version: v2
+    spec:
+      containers:
+        - name: helloworld
+          image: httpd
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent
+          ports:
+            - containerPort: 80
+```
+
+
+## Gateway
+
+Deploys an Istio gateway that's listening to the port `80` for `HTTP` traffic.
+
+It doesn't filter for any specific host.
+
+The `selector` field is used to "choose" which Istio Load Balancers will have this gateway assigned to.
+
+The Istio `default` profile creates a Load Balancer in the namespace `istio-system` that has the label `istio: ingressgateway` set, allowing us to target that specific Load Balancer and assign this gateway resource to it.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+  namespace: default
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"
+```
+
+## VirtualService
+
+The configuration set, targets the [gateway created](#gateway) as well of not limiting the traffic to any specific host.
+
+We will create 3 rules that target `HTTP` (including `HTTPS` and `HTTP2` traffic), which are declared with the following names:
+
+- firefox
+- curl
+- default
+
+The `firefox` rule is intended to receive traffic coming from a Firefox web browser.
+
+The `curl` rule is intended to receive traffic coming from the `curl` command line package/command.  
+
+The `default` rule is intended to receive traffic not matched by the 2 rules of above (as long meets certain criteria).
+
+All the rules created will match on the following topics:
+
+- The path directory will be `/helloworld`.
+
+- The destination service will be `helloworld.default.svc.cluster.local` to the port `80`.
+
+- Rewrite URL path to `/` to not create conflicts with the backend.
+
+The rules will differ on the following topics:
+
+- Each rule will target a specific content from the header `user-agent`, except of default.
+
+- Each rule will target a different `subset` to distribute the traffic between the [Deployment resources created](#deployment).
+
+> **Note**\
+> If you usage not familiar with the usage of `subsets`, I strongly recommend to check the following example:
+> - [03-hello_world_1_service_2_deployments_managed_version](../../01-Getting_Started/03-hello_world_1_service_2_deployments_managed_version) 
+
+> **Note**\
+> The declaration order from the resources is important, as the elements created further above on the list will have priority over the rules set under them.\
+> This would mean that if we declared the `default` matching rule first, it would overtake the traffic meant to reach the rules `firefox` and `curl`.
+> For more information regarding this matter, refer to the following Official Istio documentation regarding [the HttpMatchRequest field from Istio VirtualServices](https://istio.io/latest/docs/reference/config/networking/virtual-service/#HTTPMatchRequest).
+
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - name: firefox
+      match:
+        - uri:
+            exact: /helloworld
+          headers:
+            user-agent:
+              regex: '.*Firefox.*'
+      route:
+        - destination:
+            host: helloworld.default.svc.cluster.local
+            port:
+              number: 80
+            subset: nginx
+      rewrite:
+        uri: "/"
+    - name: curl
+      match:
+        - headers:
+            user-agent:
+              regex: '.*curl.*'
+          uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld.default.svc.cluster.local
+            port:
+              number: 80
+            subset: apache
+      rewrite:
+        uri: "/"
+    - name: default
+      match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld.default.svc.cluster.local
+            port:
+              number: 80
+            subset: default
+      rewrite:
+        uri: "/"
+```
+
+## DestinationRule
+
+This `DestinationRule` interferes with the traffic with destination `helloworld.default.svc.cluster.local`.
+
+Contains 3 subsets defined, where each one will target a different backend.
+
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: DestinationRule
+metadata:
+  name: helloworld.default.svc.cluster.local # Destination that will "interject"
+spec:
+  host: helloworld.default.svc.cluster.local # Full destination service, lil better for consistency
+  subsets:
+    - name: default
+      labels:
+        version: v0
+    - name: nginx
+      labels:
+        version: v1
+    - name: apache
+      labels:
+        version: v2
+```
+
+# Walkthrough
+
+## Deploy resources
+
+Deploy the resources.
+
+```shell
+kubectl apply -f ./
+```
+```text 
+deployment.apps/helloworld-v0 created
+deployment.apps/helloworld-v1 created
+deployment.apps/helloworld-v2 created
+destinationrule.networking.istio.io/helloworld.default.svc.cluster.local created
+gateway.networking.istio.io/helloworld-gateway created
+service/helloworld created
+virtualservice.networking.istio.io/helloworld-vs created
+```
+
+## Wait for the pods to be ready
+
+Wait for the Apache, Nginx and Whoami deployments to be up and ready.
+
+```shell
+watch -n 2 kubectl get deployment helloworld-v{0..2} 
+```
+```text 
+NAME            READY   UP-TO-DATE   AVAILABLE   AGE
+helloworld-v0   1/1     1            1           23s
+helloworld-v1   1/1     1            1           23s
+helloworld-v2   1/1     1            1           23s
+```
+
+## Test the service
+
+Now it's time to test the rules created in the [VirtualService configuration](#virtualservice), for such reminder that:
+
+- Curl should return traffic from the Apache deployment.
+- Firefox should return traffic from the Nginx deployment.
+- The rest of the traffic should return us a response from the Whoami deployment. (as long it matches the rest of criteria set in the rule).
+
+### Get LB IP
+
+To perform the desired tests, we will need to obtain the IP Istio Load Balancer that we selected in the [Gateway section](#gateway).
+
+On my environment, the IP is the `192.168.1.50`.
+
+```shell
+kubectl get svc -l istio=ingressgateway -A
+```
+```text
+NAME                   TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)                                      AGE
+istio-ingressgateway   LoadBalancer   10.97.47.216   192.168.1.50   15021:31316/TCP,80:32012/TCP,443:32486/TCP   39h
+```
+
+### Curl
+
+Using the command `curl`, results in receiving content from the Apache deployment.
+
+```text
+curl 192.168.1.50/helloworld -s                     
+```
+```text
+<html><body><h1>It works!</h1></body></html>
+```
+
+### Firefox browser
+
+Through using the Firefox web browser, the page accessed is the Nginx deployment. 
+
+![firefox.png](./src/firefox.png)
+
+### Default
+To trigger the "default" rule, you can be quite creative there, like using another browser some other tool.
+
+In my case I will be using the package `wget` as it is more simple for myself.
+
+
+```shell
+wget 192.168.1.50/helloworld -O /dev/stdout -q
+```
+
+```text
+Hostname: helloworld-v0-64fc7d6ccb-vdljp
+IP: 127.0.0.1
+IP: ::1
+IP: 172.17.247.19
+IP: fe80::dc11:59ff:fe15:f6c3
+RemoteAddr: 127.0.0.6:51179
+GET / HTTP/1.1
+Host: 192.168.1.50
+User-Agent: Wget/1.21.3
+Accept: */*
+Accept-Encoding: identity
+X-B3-Parentspanid: 7a17876e5182b4a1
+X-B3-Sampled: 0
+X-B3-Spanid: 0aa085397844c696
+X-B3-Traceid: 3c9474b384a9f33c7a17876e5182b4a1
+X-Envoy-Attempt-Count: 1
+X-Envoy-Internal: true
+X-Envoy-Original-Path: /helloworld
+X-Forwarded-Client-Cert: By=spiffe://cluster.local/ns/default/sa/default;Hash=bf05b3ab5654afeecc50ea6b136708517bcfdec088978a2a675759d52aa207aa;Subject="";URI=spiffe://cluster.local/ns/istio-system/sa/istio-ingressgateway-service-account
+X-Forwarded-For: 192.168.1.10
+X-Forwarded-Proto: http
+X-Request-Id: 46d7dbe8-ba46-4703-b1a3-cdecf2f93d1e
+```
+
+
+## Cleanup
+
+Finally, a cleanup from the resources deployed.
+
+```shell
+kubectl delete -f ./
+```
+```text
+deployment.apps "helloworld-v0" deleted
+deployment.apps "helloworld-v1" deleted
+deployment.apps "helloworld-v2" deleted
+destinationrule.networking.istio.io "helloworld.default.svc.cluster.local" deleted
+gateway.networking.istio.io "helloworld-gateway" deleted
+service "helloworld" deleted
+```
+
+
+
+# Links of interest
+
+- https://istio.io/latest/docs/reference/config/networking/virtual-service/
+
+- https://istio.io/latest/docs/reference/config/networking/virtual-service/#HTTPMatchRequest
+
+- https://istio.io/latest/docs/reference/config/networking/destination-rule/#

02-Traffic_management/01-header_routing/Service.yaml

@@ -0,0 +1,13 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld

02-Traffic_management/01-header_routing/VirtualService.yaml

@@ -1,19 +1,3 @@
-# https://github.com/istio/istio/blob/master/samples/helloworld/helloworld-gateway.yaml
-apiVersion: networking.istio.io/v1alpha3
-kind: Gateway
-metadata:
-  name: helloworld-gateway
-spec:
-  selector:
-    istio: ingressgateway # use istio default controller
-  servers:
-    - port:
-        number: 80
-        name: http
-        protocol: HTTP
-      hosts:
-        - "*"
----
 apiVersion: networking.istio.io/v1alpha3
 kind: VirtualService
 metadata:
@@ -56,8 +40,8 @@ spec:
         uri: "/"
     - name: default
       match:
-          - uri:
-              exact: /helloworld
+        - uri:
+            exact: /helloworld
       route:
         - destination:
             host: helloworld.default.svc.cluster.local
@@ -65,21 +49,4 @@ spec:
               number: 80
             subset: default
       rewrite:
-        uri: "/"
----
-apiVersion: networking.istio.io/v1alpha3
-kind: DestinationRule
-metadata:
-  name: helloworld.default.svc.cluster.local # Destination that will "interject"
-spec:
-  host: helloworld.default.svc.cluster.local # Full destination service, lil better for consistency
-  subsets:
-    - name: default
-      labels:
-        version: v0
-    - name: nginx
-      labels:
-        version: v1
-    - name: apache
-      labels:
-        version: v2
+        uri: "/"

02-Traffic_management/02-DirectResponse-HTTP-Body/Deployment.yaml

@@ -1,17 +1,3 @@
-apiVersion: v1
-kind: Service
-metadata:
-  name: helloworld
-  labels:
-    app: helloworld
-    service: helloworld
-spec:
-  ports:
-    - port: 80
-      name: http
-  selector:
-    app: helloworld
----
 apiVersion: apps/v1
 kind: Deployment
 metadata:

02-Traffic_management/02-DirectResponse-HTTP-Body/Gateway.yaml

@@ -0,0 +1,14 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"

02-Traffic_management/02-DirectResponse-HTTP-Body/README.md

@@ -0,0 +1,282 @@
+---
+gitea: none
+include_toc: true
+---
+
+# Description
+
+Based on the [previous example](../../01-Getting_Started/01-hello_world_1_service_1_deployment), we configure the [VirtualService](#virtualservice) to return a specific response to the client with the contents of our choice.
+
+This example configures:
+
+    Generic Kubernetes resources:
+    - 1 Service
+    - 1 Deployments
+    
+    Istio resources:
+    - 1 Gateway
+    - 1 Virtual Service
+
+
+# Based on
+
+- [01-hello_world_1_service_1_deployment](../../01-Getting_Started/01-hello_world_1_service_1_deployment)
+
+# Configuration
+
+## Service
+
+Creates a service named `helloworld`.
+
+This service listens for the port `80` expecting `HTTP` traffic and will forward the incoming traffic towards the port `80` from the destination pod.
+
+```yaml
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld
+```
+
+## Deployment
+
+Deploys a Nginx server that listens for the port `80`.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-nginx
+  labels:
+    app: helloworld
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+  template:
+    metadata:
+      labels:
+        app: helloworld
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent #Always
+          ports:
+            - containerPort: 80
+```
+
+## Gateway
+
+Deploys an Istio gateway that's listening to the port `80` for `HTTP` traffic.
+
+It doesn't filter for any specific host.
+
+The `selector` field is used to "choose" which Istio Load Balancers will have this gateway assigned to.
+
+The Istio `default` profile creates a Load Balancer in the namespace `istio-system` that has the label `istio: ingressgateway` set, allowing us to target that specific Load Balancer and assign this gateway resource to it.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"
+```
+
+## VirtualService
+
+The configuration set, targets the [gateway created](#gateway) as well of not limiting the traffic to any specific host.
+
+We configure 2 rules for HTTP traffic (this includes `HTTPS` and `HTTP2`, this will be my last warning about this).
+
+The first rule configured will match when the requested path is `/helloworld`.
+
+This traffic will be forwarded to the service `helloworld.default.svc.cluster.local` with port `80`.
+
+The second rule, which will manage the rest of the traffic, will return a response with status code `404`, and body content set to `Page Not Found`.
+
+Additionally, for consistency and good practices purposes, we also specified the content type of the page to `text/plain`. 
+
+```yaml
+apiVersion: networking.istio.io/v1beta1
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - name: helloworld
+      match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld.default.svc.cluster.local
+            port:
+              number: 80
+      rewrite:
+        uri: "/"
+    - name: default
+      directResponse:
+        status: 404
+        body:
+          string: "Page Not Found"
+      headers:
+        response:
+          set:
+            content-type: "text/plain"
+```
+
+# Walkthrough
+
+## Deploy resources
+
+Deploy the resources.
+
+```shell
+kubectl apply -f ./
+```
+```text 
+deployment.apps/helloworld-nginx created
+gateway.networking.istio.io/helloworld-gateway created
+service/helloworld created
+virtualservice.networking.istio.io/helloworld-vs created
+```
+
+## Wait for the pods to be ready
+
+Wait for the Apache and Nginx deployments to be up and ready.
+
+```shell
+kubectl get deployment helloworld-nginx -w
+```
+```text 
+NAME               READY   UP-TO-DATE   AVAILABLE   AGE
+helloworld-nginx   1/1     1            1           9s
+```
+
+## Test the service
+
+### Get LB IP
+
+To perform the desired tests, we will need to obtain the IP Istio Load Balancer that we selected in the [Gateway section](#gateway).
+
+On my environment, the IP is the `192.168.1.50`.
+
+```shell
+kubectl get svc -l istio=ingressgateway -A
+```
+```text
+NAME                   TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)                                      AGE
+istio-ingressgateway   LoadBalancer   10.97.47.216   192.168.1.50   15021:31316/TCP,80:32012/TCP,443:32486/TCP   39h
+```
+
+### helloworld
+
+As expected, we receive the contents from the Nginx contents
+
+```shell
+curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+```
+```text
+<h1>Welcome to nginx!</h1>
+```
+### other paths
+
+#### /
+
+We receive the contents "Page Not Found".
+
+```shell
+curl 192.168.1.50/   
+```
+
+```text
+Page Not Found 
+```
+
+Checking the headers, we also can see the status code is set to `404`, as well of the content-type we specified on the [VirtualService configuration](#virtualservice).
+
+```shell
+curl 192.168.1.50/ -I   
+```
+
+```text
+HTTP/1.1 404 Not Found
+content-type: text/plain
+content-length: 14
+date: Thu, 04 May 2023 01:18:50 GMT
+server: istio-envoy
+```
+
+
+
+#### /found
+
+We can confirm that this behavior applies to other paths (as it is matching the "default" rule we set in [VirtualService configuration]).
+
+```shell
+curl 192.168.1.50/found
+```
+
+```text
+Page Not Found
+```
+
+```shell
+curl 192.168.1.50/found -I   
+```
+
+```text
+HTTP/1.1 404 Not Found
+content-type: text/plain
+content-length: 14
+date: Thu, 04 May 2023 01:20:40 GMT
+server: istio-envoy
+```
+
+
+## Cleanup
+
+Finally, a cleanup from the resources deployed.
+
+```shell
+kubectl delete -f ./
+```
+```text
+deployment.apps "helloworld-nginx" deleted
+gateway.networking.istio.io "helloworld-gateway" deleted
+service "helloworld" deleted
+virtualservice.networking.istio.io "helloworld-vs" deleted
+```
+
+# Links of interest
+
+- https://istio.io/latest/docs/reference/config/networking/virtual-service/#HTTPDirectResponse
+
+- https://istio.io/latest/docs/reference/config/networking/virtual-service/#HTTPBody

02-Traffic_management/02-DirectResponse-HTTP-Body/Service.yaml

@@ -0,0 +1,13 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld

02-Traffic_management/02-DirectResponse-HTTP-Body/VirtualService.yaml

@@ -1,19 +1,3 @@
-# https://github.com/istio/istio/blob/master/samples/helloworld/helloworld-gateway.yaml
-apiVersion: networking.istio.io/v1alpha3
-kind: Gateway
-metadata:
-  name: helloworld-gateway
-spec:
-  selector:
-    istio: ingressgateway # use istio default controller
-  servers:
-    - port:
-        number: 80
-        name: http
-        protocol: HTTP
-      hosts:
-        - "*"
----
 apiVersion: networking.istio.io/v1beta1
 kind: VirtualService
 metadata:
@@ -30,7 +14,7 @@ spec:
             exact: /helloworld
       route:
         - destination:
-            host: helloworld
+            host: helloworld.default.svc.cluster.local
             port:
               number: 80
       rewrite:

02-Traffic_management/03-HTTPRewrite/Deployment.yaml

@@ -1,17 +1,3 @@
-apiVersion: v1
-kind: Service
-metadata:
-  name: helloworld
-  labels:
-    app: helloworld
-    service: helloworld
-spec:
-  ports:
-    - port: 80
-      name: http
-  selector:
-    app: helloworld
----
 apiVersion: apps/v1
 kind: Deployment
 metadata:

02-Traffic_management/03-HTTPRewrite/README.md

@@ -0,0 +1,240 @@
+---
+gitea: none
+include_toc: true
+---
+
+# Description
+
+Based on the [previous example](../../01-Getting_Started/01-hello_world_1_service_1_deployment), we configure the [VirtualService](#virtualservice) to internally rewrite the destination URL.
+
+This is useful, as if for example we have a rule that targets the traffic with destination path `/helloworld`, when we connect to the backend, the path that the request contains will also be `/helloworld`, and unless the destination service is already build around this and/or is ready to manage traffic with such destination, we will receive a status code 404 meaning that the page destination was not found.
+
+If we internally rewrite such traffic to the root directory (`/`), we can interact with the root path from the destination service without issues, without the need of specifically altering the behavior of the destination service due this architectural requirement.
+
+Additionally, we also configure a second rule that won't have the URL path rewrite configured, as it will allow us to compare the behaviors.  
+
+This example configures:
+
+    Generic Kubernetes resources:
+    - 1 Service
+    - 1 Deployments
+    
+    Istio resources:
+    - 1 Gateway
+    - 1 Virtual Service
+
+
+# Based on
+
+- [01-hello_world_1_service_1_deployment](../../01-Getting_Started/01-hello_world_1_service_1_deployment)
+
+# Configuration
+
+## Service
+
+Creates a service named `helloworld`.
+
+This service listens for the port `80` expecting `HTTP` traffic and will forward the incoming traffic towards the port `80` from the destination pod.
+
+```yaml
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld
+```
+
+## Deployment
+
+Deploys a Nginx server that listens for the port `80`.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-nginx
+  labels:
+    app: helloworld
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+  template:
+    metadata:
+      labels:
+        app: helloworld
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent #Always
+          ports:
+            - containerPort: 80
+```
+
+## Gateway
+
+Deploys an Istio gateway that's listening to the port `80` for `HTTP` traffic.
+
+It doesn't filter for any specific host.
+
+The `selector` field is used to "choose" which Istio Load Balancers will have this gateway assigned to.
+
+The Istio `default` profile creates a Load Balancer in the namespace `istio-system` that has the label `istio: ingressgateway` set, allowing us to target that specific Load Balancer and assign this gateway resource to it.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"
+```
+
+## VirtualService
+
+The configuration set, targets the [gateway created](#gateway) as well of not limiting the traffic to any specific host.
+
+We configure 2 HTTP rules.
+
+The first rule will match when the requested path is `/helloworld`.
+
+Internally, we will rewrite the URL path, from `/helloworld` to `/`, as otherwise it will result in status code 404 due not containing such destination in the service, since we are using the default Nginx image.
+
+The second rule will math with the path `/norewrite`, and won't have the rewrite URL path setting configured. This rule will be used to compare behaviors.
+
+
+Both rules will connect with the backend service `helloworld.default.svc.cluster.local` with port `80`.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld.default.svc.cluster.local
+            port:
+              number: 80
+    - match:
+        - uri:
+            exact: /norewrite
+      route:
+        - destination:
+            host: helloworld.default.svc.cluster.local
+            port:
+              number: 80
+```
+
+# Walkthrough
+
+## Deploy resources
+
+Deploy the resources.
+
+```shell
+kubectl apply -f ./
+```
+```text 
+deployment.apps/helloworld-nginx created
+service/helloworld created
+virtualservice.networking.istio.io/helloworld-vs created
+gateway.networking.istio.io/helloworld-gateway created
+```
+
+## Wait for the pods to be ready
+
+Wait for the Nginx deployment to be up and ready.
+
+```shell
+kubectl get deployment helloworld-nginx -w
+```
+```text 
+NAME               READY   UP-TO-DATE   AVAILABLE   AGE
+helloworld-nginx   1/1     1            1           2m47s
+```
+
+## Test the service
+
+### Get LB IP
+
+To perform the desired tests, we will need to obtain the IP Istio Load Balancer that we selected in the [Gateway section](#gateway).
+
+On my environment, the IP is the `192.168.1.50`.
+
+```shell
+kubectl get svc -l istio=ingressgateway -A
+```
+```text
+NAME                   TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)                                      AGE
+istio-ingressgateway   LoadBalancer   10.97.47.216   192.168.1.50   15021:31316/TCP,80:32012/TCP,443:32486/TCP   39h
+```
+
+### helloworld
+
+Due to rewriting the URL path internally, we are able to connect to the backend root path (`/`) 
+
+```shell
+curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+```
+```text
+<h1>Welcome to nginx!</h1>
+```
+
+### norewrite
+
+As expected, due the backend service not having a destination path named `/norewrite`, we receive a status code 404 as well of their pertinent service error page.
+
+```shell
+curl 192.168.1.50/helloworld -s | grep "<h1>.*</h1>" 
+```
+```text
+<center><h1>404 Not Found</h1></center>
+```
+
+## Cleanup`
+
+Finally, a cleanup from the resources deployed.
+
+```shell
+kubectl delete -f ./
+```
+```text
+deployment.apps "helloworld-nginx" deleted
+service "helloworld" deleted
+virtualservice.networking.istio.io "helloworld-vs" deleted
+gateway.networking.istio.io "helloworld-gateway" deleted
+```
+
+# Links of interest
+
+- https://istio.io/latest/docs/reference/config/networking/virtual-service/#HTTPRewrite

02-Traffic_management/03-HTTPRewrite/Service.yaml

@@ -0,0 +1,13 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld

02-Traffic_management/03-HTTPRewrite/VirtualService.yaml

@@ -0,0 +1,26 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld.default.svc.cluster.local
+            port:
+              number: 80
+    - match:
+        - uri:
+            exact: /norewrite
+      route:
+        - destination:
+            host: helloworld.default.svc.cluster.local
+            port:
+              number: 80

02-Traffic_management/03-HTTPRewrite/gateway.yaml

@@ -0,0 +1,14 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"

02-Traffic_management/04-HTTPRedirect/Gateway.yaml

@@ -0,0 +1,14 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"

02-Traffic_management/04-HTTPRedirect/README.md

@@ -0,0 +1,255 @@
+---
+gitea: none
+include_toc: true
+---
+
+# Description
+
+Based on the [previous example](../../01-Getting_Started/01-hello_world_1_service_1_deployment), we create multiple rules in the [VirtualService](#virtualservice) that will make usage of the `redirect` field to modify the request received and redirect the incoming request towards a new destination.
+
+This example configures:
+
+    Istio resources:
+    - 1 Gateway
+    - 1 Virtual Service
+
+# Based on
+
+- [01-hello_world_1_service_1_deployment](../../01-Getting_Started/01-hello_world_1_service_1_deployment)
+
+# Configuration
+
+## Gateway
+
+Deploys an Istio gateway that's listening to the port `80` for `HTTP` traffic.
+
+It doesn't filter for any specific host.
+
+The `selector` field is used to "choose" which Istio Load Balancers will have this gateway assigned to.
+
+The Istio `default` profile creates a Load Balancer in the namespace `istio-system` that has the label `istio: ingressgateway` set, allowing us to target that specific Load Balancer and assign this gateway resource to it.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"
+```
+
+## VirtualService
+
+The configuration set, targets the [gateway created](#gateway) as well of not limiting the traffic to any specific host.
+
+We configure 3 HTTP rules.
+
+- to_https
+
+A practical example regarding modifying protocol used from the incoming traffic request.
+
+It will set the protocol used to `HTTPS`.
+
+> **Note:**\
+> Bear in mind that this example is not planned to be used `as it is` on production environments as other configurations should be applied, as an example you should target a specific source port.
+
+- wikipedia
+
+We are using the regex query `/wiki/?` to match the URL path, this rule allows us to target both `/wiki` and `/wiki/`.
+
+On this example we will redirect the traffic that accesses to this rule towards the Wikipedia page, as well the protocol will be modified and set to `HTTPS`.
+
+- wikipedia_search
+
+Very similar to the previous rule, we will match the traffic that, as a prefix of the URl used, as long it starts by `/wiki/`.
+
+More information about the behavior of ties rule will be seen in the [Walkthrough](#walkthrough) section. 
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - name: to_https
+      match:
+        - uri:
+            exact: /https
+      redirect:
+        scheme: "https"
+
+    - name: wikipedia
+      match:
+        - uri:
+            regex: "/wiki/?"
+      redirect:
+        uri: "/"
+        scheme: "https"
+        authority: "en.wikipedia.org"
+
+    - name: wikipedia_search
+      match:
+        - uri:
+            prefix: "/wiki/"
+      redirect:
+        scheme: "https"
+        authority: "en.wikipedia.org"
+```
+
+# Walkthrough
+
+## Deploy resources
+
+Deploy the resources.
+
+```shell
+kubectl apply -f ./
+```
+```text 
+gateway.networking.istio.io/helloworld-gateway created
+virtualservice.networking.istio.io/helloworld-vs created
+```
+
+## Test the rules
+
+### Get LB IP
+
+To perform the desired tests, we will need to obtain the IP Istio Load Balancer that we selected in the [Gateway section](#gateway).
+
+On my environment, the IP is the `192.168.1.50`.
+
+```shell
+kubectl get svc -l istio=ingressgateway -A
+```
+```text
+NAME                   TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)                                      AGE
+istio-ingressgateway   LoadBalancer   10.97.47.216   192.168.1.50   15021:31316/TCP,80:32012/TCP,443:32486/TCP   39h
+```
+
+### to_https
+
+We are receiving the status code `301` as the request is being modified.
+
+By default `curl` won't follow the redirects. 
+
+```shell
+curl 192.168.1.50/https -I
+```
+```text
+HTTP/1.1 301 Moved Permanently
+location: https://192.168.1.50/https
+date: Fri, 05 May 2023 00:15:41 GMT
+server: istio-envoy
+transfer-encoding: chunked
+```
+ 
+The flag `-L` can be used to allow `curl` to follow redirects, as well of `-v` to increase the verbosity to review the behavior.
+
+From the output received, we can see how the request initially points towards the port `80`.
+
+After receiving the status code `301`, we can see the following line `Clear auth, redirects to port from 80 to 443`, stating that there was a redirect that changed the destination port, from `80`, to `443`.
+
+As well, there is the line `Issue another request to this URL: 'https://192.168.1.50/https'`, which confirms that the protocol used, which previously was using `HTTP`, now is using `HTTPS`.
+
+This proves that the configuration set is currently being applied and works as intended.
+
+```shell
+curl 192.168.1.50/https -L -v
+```
+
+```text
+*   Trying 192.168.1.50:80...
+* Connected to 192.168.1.50 (192.168.1.50) port 80 (#0)
+> GET /https HTTP/1.1
+> Host: 192.168.1.50
+> User-Agent: curl/8.0.1
+> Accept: */*
+> 
+< HTTP/1.1 301 Moved Permanently
+< location: https://192.168.1.50/https
+< date: Fri, 05 May 2023 00:17:12 GMT
+< server: istio-envoy
+< content-length: 0
+< 
+* Connection #0 to host 192.168.1.50 left intact
+* Clear auth, redirects to port from 80 to 443
+* Issue another request to this URL: 'https://192.168.1.50/https'
+*   Trying 192.168.1.50:443...
+* connect to 192.168.1.50 port 443 failed: Connection refused
+* Failed to connect to 192.168.1.50 port 443 after 0 ms: Couldn't connect to server
+* Closing connection 1
+curl: (7) Failed to connect to 192.168.1.50 port 443 after 0 ms: Couldn't connect to server
+```
+
+### /wiki/
+
+On this example I will be using the Firefox browser to access the destination path `/wiki/`.  
+
+Which on accessing the path, it modified the request and forwarded the traffic towards the path `https://en.wikipedia.org/wiki`.
+
+After accessing such destination, Wikipedia will forward you to the path `/wiki/Main_Page`, as we didn't target any specific element from the wiki.
+
+```shell
+firefox 192.168.1.50/wiki/
+```
+![img.png](src/img.png)
+
+### /wiki/*
+
+On this example I will be using the Firefox browser to access the destination path `/wiki/Istio` and `/wiki/Gitea`.
+
+This will forward us towards the pertinent wiki service, as meanwhile the domain is modified, the path remains the same, allowing us to match the right destination paths.
+
+```shell
+firefox 192.168.1.50/wiki/Service_mesh
+```
+
+![img_1.png](src/img_1.png)
+
+```shell
+firefox 192.168.1.50/wiki/Gitea
+```
+
+![img_2.png](src/img_2.png)
+
+
+## Cleanup
+
+Finally, a cleanup from the resources deployed.
+
+```shell
+kubectl delete -f ./
+```
+```text
+gateway.networking.istio.io "helloworld-gateway" deleted
+virtualservice.networking.istio.io "helloworld-vs" deleted
+```
+
+# Links of interest
+
+- https://istio.io/latest/docs/reference/config/networking/virtual-service/#HTTPRedirect
+
+
+
+
+
+
+
+
+
+
+
+

02-Traffic_management/04-HTTPRedirect/VirtualService.yaml

@@ -0,0 +1,33 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - name: to_https
+      match:
+        - uri:
+            exact: /https
+      redirect:
+        scheme: "https"
+
+    - name: wikipedia
+      match:
+        - uri:
+            regex: "/wiki/?"
+      redirect:
+        uri: "/"
+        scheme: "https"
+        authority: "en.wikipedia.org"
+
+    - name: wikipedia_search
+      match:
+        - uri:
+            prefix: "/wiki/"
+      redirect:
+        scheme: "https"
+        authority: "en.wikipedia.org"

02-Traffic_management/README.md

@@ -0,0 +1,12 @@
+# Description
+
+This section involves the configuration of `Virtual Service` objects.
+
+# Examples
+
+- 01-header_routing
+- 02-DirectResponse-HTTP-Body
+- 03-HTTPRewrite
+- 04-HTTPRedirect
+
+

03-Gateway_Ingress/01-Host_Based_Routing/Deployment.yaml

@@ -1,17 +1,3 @@
-## https://github.com/istio/istio/blob/master/samples/helloworld/helloworld.yaml
-apiVersion: v1
-kind: Service
-metadata:
-  name: helloworld
-  labels:
-    app: helloworld
-spec:
-  ports:
-    - port: 8080
-      name: http
-  selector:
-    app: helloworld
----
 apiVersion: apps/v1
 kind: Deployment
 metadata:

03-Gateway_Ingress/01-Host_Based_Routing/Gateway.yaml

@@ -0,0 +1,14 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "my.domain"

03-Gateway_Ingress/01-Host_Based_Routing/README.md

@@ -0,0 +1,238 @@
+---
+gitea: none
+include_toc: true
+---
+
+# Description
+
+This example deploys the same infrastructure as the [previous example](../../01-Getting_Started/01-hello_world_1_service_1_deployment), and restricts the access to the gateway based on the domain host from the destination URL.
+
+The domain host targeted will be `my.domain`.
+
+This example configures:
+
+    Generic Kubernetes resources:
+    - 1 Service
+    - 1 Deployment
+    
+    Istio resources:
+    - 1 Gateway
+    - 1 Virtual Service
+
+> **Note:**\
+> I don't intend to explain thing related to Kubernetes unless necessary.
+
+
+# Based on
+
+- [01-hello_world_1_service_1_deployment](../../01-Getting_Started/01-hello_world_1_service_1_deployment)
+
+# Configuration
+
+## Service
+
+Creates a service named `helloworld`.
+
+This service listens for the port `80` expecting `HTTP` traffic and will forward the incoming traffic towards the port `80` from the destination pod.
+
+```yaml
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld
+```
+
+## Deployment
+
+Deploys a Nginx server that listens for the port `80`.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-nginx
+  labels:
+    app: helloworld
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+  template:
+    metadata:
+      labels:
+        app: helloworld
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent #Always
+          ports:
+            - containerPort: 80
+```
+
+## Gateway
+
+Deploys an Istio gateway that's listening to the port `80` for `HTTP` traffic.
+
+The gateway only will allow the traffic that uses as a URL host: `my.domain`.
+
+The `selector` field is used to "choose" which Istio Load Balancers will have this gateway assigned to.
+
+The Istio `default` profile creates a Load Balancer in the namespace `istio-system` that has the label `istio: ingressgateway` set, allowing us to target that specific Load Balancer and assign this gateway resource to it.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "my.domain"
+```
+
+## VirtualService
+
+The Virtual Service resources are used to route and filter the received traffic from the gateway resources, and route it towards the desired destination.
+
+On this example we select the gateway `helloworld-gateway`, which is the [gateway that 's described in the `Gateway` section](#gateway).
+
+On this resource, we are also not limiting the incoming traffic to any specific host, allowing for all the incoming traffic to go through the rules set.
+
+Here we created a rule that will be applied on `HTTP` related traffic (including `HTTPS` and `HTTP2`) when the destination path is exactly `/helloworld`.
+
+This traffic will be forwarded to the port `80` of the destination service `helloworld` (the full path URL equivalent would be `helloworld.$NAMESPACE.svc.cluster.local`).
+
+Additionally, there will be an internal URL rewrite set, as if the URL is not modified, it would attempt to reach to the `/helloworld` path from the Nginx deployment, which currently has no content and would result in an error code `404` (Not found).
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld
+            port:
+              number: 80
+      rewrite:
+        uri: "/"
+```
+
+# Walkthrough
+
+## Deploy resources
+
+Deploy the resources.
+
+```shell
+kubectl apply -f ./ 
+```
+```text
+deployment.apps/helloworld-nginx created
+gateway.networking.istio.io/helloworld-gateway created
+service/helloworld created
+virtualservice.networking.istio.io/helloworld-vs created
+```
+
+## Wait for the deployment to be ready
+
+Wait for the Nginx deployment to be up and ready.
+
+```shell
+kubectl get deployment helloworld-nginx -w 
+```
+```text
+NAME               READY   UP-TO-DATE   AVAILABLE   AGE
+helloworld-nginx   1/1     1            1           44s
+```
+
+## Test the service
+
+### Get LB IP
+
+To perform the desired tests, we will need to obtain the IP Istio Load Balancer that we selected in the [Gateway section](#gateway).
+
+On my environment, the IP is the `192.168.1.50`.
+
+```shell
+kubectl get svc -l istio=ingressgateway -A
+```
+```text
+NAME                   TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)                                      AGE
+istio-ingressgateway   LoadBalancer   10.97.47.216   192.168.1.50   15021:31316/TCP,80:32012/TCP,443:32486/TCP   39h
+```
+
+### Curl /helloworld
+
+When performing a curl towards the destination path, as we are not using the domain host specified in the [gateway resource](#gateway), we are failing to match any rule.
+
+```shell
+ curl 192.168.1.50/helloworld -I
+```
+```text
+HTTP/1.1 404 Not Found
+date: Wed, 10 May 2023 08:25:26 GMT
+server: istio-envoy
+transfer-encoding: chunked
+```
+
+### Curl my.domain/helloworld
+
+We can "fake" the destination domain by modifying the `Host` header.
+
+After setting that up, and attempting to curl the destination, we receive a positive response from the Nginx backend. 
+
+```shell
+curl 192.168.1.50/helloworld -s -HHOST:my.domain | grep "<title>.*</title>"
+```
+```text
+<title>Welcome to nginx!</title>
+```
+
+
+## Cleanup
+
+Finally, a cleanup from the resources deployed.
+
+```shell
+kubectl delete -f ./
+```
+```text
+deployment.apps "helloworld-nginx" deleted
+gateway.networking.istio.io "helloworld-gateway" deleted
+service "helloworld" deleted
+virtualservice.networking.istio.io "helloworld-vs" deleted
+```
+
+# Links of interest
+
+- https://istio.io/latest/docs/reference/config/networking/gateway/

03-Gateway_Ingress/01-Host_Based_Routing/Service.yaml

@@ -0,0 +1,13 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld

03-Gateway_Ingress/01-Host_Based_Routing/VirtualService.yaml

@@ -0,0 +1,20 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld
+            port:
+              number: 80
+      rewrite:
+        uri: "/"

03-Gateway_Ingress/02-Restrict_Namespaces/01-namespace.yaml

@@ -0,0 +1,4 @@
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: foo

03-Gateway_Ingress/02-Restrict_Namespaces/Deployment.yaml

@@ -0,0 +1,25 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-nginx
+  labels:
+    app: helloworld
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+  template:
+    metadata:
+      labels:
+        app: helloworld
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent #Always
+          ports:
+            - containerPort: 80

03-Gateway_Ingress/02-Restrict_Namespaces/Gateway.yaml

@@ -0,0 +1,14 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway
+  servers:
+    - port:
+        number: 80
+        name: http-b
+        protocol: HTTP
+      hosts:
+        - "foo/*"

03-Gateway_Ingress/02-Restrict_Namespaces/README.md

@@ -0,0 +1,294 @@
+---
+gitea: none
+include_toc: true
+---
+
+# Description
+
+This example deploys the same infrastructure as the [previous example](../../01-Getting_Started/01-hello_world_1_service_1_deployment), and restrict which `VirtualService` Istio resources can access/select the `Gateway` Istio resource, based on the `VirtualService` namespace.
+
+The domain host targeted will be `my.domain`.
+
+This example configures:
+
+    Generic Kubernetes resources:
+    - 1 Service
+    - 1 Deployment
+    - 1 Namespace
+    
+    Istio resources (`default` namespace):
+    - 1 Gateway
+    -  Virtual Service
+
+    Istio resources (`foo`namespace):
+    - 1 Virtual Service
+
+> **Note:**\
+> I don't intend to explain thing related to Kubernetes unless necessary.
+
+# Based on
+
+- [01-hello_world_1_service_1_deployment](../../01-Getting_Started/01-hello_world_1_service_1_deployment)
+
+# Configuration
+
+## Service
+
+Creates a service named `helloworld`.
+
+This service listens for the port `80` expecting `HTTP` traffic and will forward the incoming traffic towards the port `80` from the destination pod.
+
+```yaml
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld
+```
+
+## Deployment
+
+Deploys a Nginx server that listens for the port `80`.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-nginx
+  labels:
+    app: helloworld
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+  template:
+    metadata:
+      labels:
+        app: helloworld
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent #Always
+          ports:
+            - containerPort: 80
+```
+
+## Namespace
+
+Creates a namespace named `foo`.
+
+```yaml
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: foo
+```
+
+## Gateway
+
+Deploys an Istio gateway that's listening to the port `80` for `HTTP` traffic.
+
+The gateway won't target any specific host domain, yet limits the `VirtualService` Istio resources that can target this gateway, limiting its access to the `VirtualServices` Istio resources created in the `foo` namespace.
+
+The `selector` field is used to "choose" which Istio Load Balancers will have this gateway assigned to.
+
+The Istio `default` profile creates a Load Balancer in the namespace `istio-system` that has the label `istio: ingressgateway` set, allowing us to target that specific Load Balancer and assign this gateway resource to it.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway
+  servers:
+    - port:
+        number: 80
+        name: http-b
+        protocol: HTTP
+      hosts:
+        - "foo/*"
+```
+
+## VirtualService
+
+We will create two `VirtualServices` with the same configuration, only difference will be the namespace they are created onto (and the destination path), this will be used to test if the [`Gateway` namespace restriction configured](#gateway) is being applied to the `VirtualService` resources as desired. 
+
+On this example we select the gateway `helloworld-gateway`, which is the [gateway that 's described in the `Gateway` section](#gateway).
+
+On this resource, we are also not limiting the incoming traffic to any specific host, allowing for all the incoming traffic to go through the rules set.
+
+Additionally, there will be an internal URL rewrite set, as if the URL is not modified, it would attempt to reach to the `/helloworld` path from the Nginx deployment, which currently has no content and would result in an error code `404` (Not found).
+
+
+## helloworld-foo
+
+`VirtualService` created in the namespace `foo`.
+
+Here we created a rule that will be applied on `HTTP` related traffic (including `HTTPS` and `HTTP2`) when the destination path is exactly `/helloworld`.
+
+This traffic will be forwarded to the port `80` of the destination service `helloworld.default.svc.cluster.local`.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-foo
+  namespace: foo
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - default/helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld.default.svc.cluster.local
+            port:
+              number: 80
+      rewrite:
+        uri: "/"
+```
+
+## helloworld-default
+
+`VirtualService` created in the namespace `default`.
+
+Here we created a rule that will be applied on `HTTP` related traffic (including `HTTPS` and `HTTP2`) when the destination path is exactly `/failure`.
+
+This traffic will be forwarded to the port `80` of the destination service `helloworld.default.svc.cluster.local`.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-default
+  namespace: default
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - default/helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /failure
+      route:
+        - destination:
+            host: helloworld.default.svc.cluster.local
+            port:
+              number: 80
+      rewrite:
+        uri: "/"
+```
+
+# Walkthrough
+
+## Deploy resources
+
+Deploy the resources.
+
+```shell
+kubectl apply -f ./ 
+```
+```text
+namespace/foo created
+deployment.apps/helloworld-nginx created
+gateway.networking.istio.io/helloworld-gateway created
+service/helloworld created
+virtualservice.networking.istio.io/helloworld-foo created
+virtualservice.networking.istio.io/helloworld-default created
+```
+
+## Wait for the deployment to be ready
+
+Wait for the Nginx deployment to be up and ready.
+
+```shell
+kubectl get deployment helloworld-nginx -w 
+```
+```text
+NAME               READY   UP-TO-DATE   AVAILABLE   AGE
+helloworld-nginx   1/1     1            1           44s
+```
+
+## Test the service
+
+### Get LB IP
+
+To perform the desired tests, we will need to obtain the IP Istio Load Balancer that we selected in the [Gateway section](#gateway).
+
+On my environment, the IP is the `192.168.1.50`.
+
+```shell
+kubectl get svc -l istio=ingressgateway -A
+```
+```text
+NAME                   TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)                                      AGE
+istio-ingressgateway   LoadBalancer   10.97.47.216   192.168.1.50   15021:31316/TCP,80:32012/TCP,443:32486/TCP   39h
+```
+
+### Curl /helloworld
+
+When performing a curl towards the destination path, as we are not using the domain host specified in the [gateway resource](#gateway), we are failing to match any rule.
+
+```shell
+ curl 192.168.1.50/helloworld -I
+```
+```text
+HTTP/1.1 404 Not Found
+date: Wed, 10 May 2023 08:25:26 GMT
+server: istio-envoy
+transfer-encoding: chunked
+```
+
+### Curl my.domain/helloworld
+
+We can "fake" the destination domain by modifying the `Host` header.
+
+After setting that up, and attempting to curl the destination, we receive a positive response from the Nginx backend. 
+
+```shell
+curl 192.168.1.50/helloworld -s -HHOST:my.domain | grep "<title>.*</title>"
+```
+```text
+<title>Welcome to nginx!</title>
+```
+
+
+## Cleanup
+
+Finally, a cleanup from the resources deployed.
+
+```shell
+kubectl delete -f ./
+```
+```text
+namespace "foo" deleted
+deployment.apps "helloworld-nginx" deleted
+gateway.networking.istio.io "helloworld-gateway" deleted
+service "helloworld" deleted
+virtualservice.networking.istio.io "helloworld-foo" deleted
+virtualservice.networking.istio.io "helloworld-default" deleted
+```
+
+# Links of interest
+
+- https://istio.io/latest/docs/reference/config/networking/gateway/

03-Gateway_Ingress/02-Restrict_Namespaces/Service.yaml

@@ -0,0 +1,13 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld

03-Gateway_Ingress/02-Restrict_Namespaces/VirtualService.yaml

@@ -0,0 +1,43 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-foo
+  namespace: foo
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - default/helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld.default.svc.cluster.local
+            port:
+              number: 80
+      rewrite:
+        uri: "/"
+---
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-default
+  namespace: default
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - default/helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /failure
+      route:
+        - destination:
+            host: helloworld.default.svc.cluster.local
+            port:
+              number: 80
+      rewrite:
+        uri: "/"

03-Gateway_Ingress/03-HTTPS-Gateway-Simple-TLS/Deployment.yaml

@@ -0,0 +1,25 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-nginx
+  labels:
+    app: helloworld
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+  template:
+    metadata:
+      labels:
+        app: helloworld
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent #Always
+          ports:
+            - containerPort: 80

03-Gateway_Ingress/03-HTTPS-Gateway-Simple-TLS/Gateway.yaml

@@ -0,0 +1,17 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway
+  servers:
+    - port:
+        number: 443
+        name: secure-http
+        protocol: HTTPS
+      hosts:
+        - "*"
+      tls:
+        mode: SIMPLE
+        credentialName: my-tls-cert-secret

03-Gateway_Ingress/03-HTTPS-Gateway-Simple-TLS/README.md

@@ -5,7 +5,7 @@ include_toc: true
 
 # Based on
 
-- [01-hello_world_1_service_1_deployment](../../01-Simple/01-hello_world_1_service_1_deployment)
+- [01-hello_world_1_service_1_deployment](../../01-Getting_Started/01-hello_world_1_service_1_deployment)
 
 # Description
 

03-Gateway_Ingress/03-HTTPS-Gateway-Simple-TLS/Service.yaml

@@ -0,0 +1,13 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld

03-Gateway_Ingress/03-HTTPS-Gateway-Simple-TLS/VirtualService.yaml

@@ -0,0 +1,20 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld
+            port:
+              number: 80
+      rewrite:
+        uri: "/"

03-Gateway_Ingress/04a-HTTPS-min-TLS-version/Deployment.yaml

@@ -0,0 +1,25 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-nginx
+  labels:
+    app: helloworld
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+  template:
+    metadata:
+      labels:
+        app: helloworld
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent #Always
+          ports:
+            - containerPort: 80

03-Gateway_Ingress/04a-HTTPS-min-TLS-version/Gateway.yaml

@@ -16,24 +16,3 @@ spec:
         mode: SIMPLE
         credentialName: my-tls-cert-secret
         minProtocolVersion: TLSV1_3
----
-apiVersion: networking.istio.io/v1alpha3
-kind: VirtualService
-metadata:
-  name: helloworld-vs
-spec:
-  hosts:
-    - "*"
-  gateways:
-    - helloworld-gateway
-  http:
-    - match:
-        - uri:
-            exact: /helloworld
-      route:
-        - destination:
-            host: helloworld
-            port:
-              number: 80
-      rewrite:
-        uri: "/"

03-Gateway_Ingress/04a-HTTPS-min-TLS-version/README.md

@@ -5,7 +5,7 @@ include_toc: true
 
 # Based on
 
-- [07-HTTPS-Gateway-Simple-TLS](../07-HTTPS-Gateway-Simple-TLS)
+- [03-HTTPS-Gateway-Simple-TLS](../03-HTTPS-Gateway-Simple-TLS)
 
 # Description
 

03-Gateway_Ingress/04a-HTTPS-min-TLS-version/Service.yaml

@@ -0,0 +1,13 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld

03-Gateway_Ingress/04a-HTTPS-min-TLS-version/VirtualService.yaml

@@ -0,0 +1,20 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld
+            port:
+              number: 80
+      rewrite:
+        uri: "/"

03-Gateway_Ingress/04b-HTTPS-max-TLS-version/Deployment.yaml

@@ -0,0 +1,25 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-nginx
+  labels:
+    app: helloworld
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+  template:
+    metadata:
+      labels:
+        app: helloworld
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent #Always
+          ports:
+            - containerPort: 80

03-Gateway_Ingress/04b-HTTPS-max-TLS-version/Gateway.yaml

@@ -16,24 +16,3 @@ spec:
         mode: SIMPLE
         credentialName: my-tls-cert-secret
         maxProtocolVersion: TLSV1_2
----
-apiVersion: networking.istio.io/v1alpha3
-kind: VirtualService
-metadata:
-  name: helloworld-vs
-spec:
-  hosts:
-    - "*"
-  gateways:
-    - helloworld-gateway
-  http:
-    - match:
-        - uri:
-            exact: /helloworld
-      route:
-        - destination:
-            host: helloworld
-            port:
-              number: 80
-      rewrite:
-        uri: "/"

03-Gateway_Ingress/04b-HTTPS-max-TLS-version/README.md

@@ -5,7 +5,7 @@ include_toc: true
 
 # Based on
 
-- [08a-HTTPS-min-TLS-version](../08a-HTTPS-min-TLS-version)
+- [04a-HTTPS-min-TLS-version](../04a-HTTPS-min-TLS-version)
 
 # Description
 

03-Gateway_Ingress/04b-HTTPS-max-TLS-version/Service.yaml

@@ -0,0 +1,13 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld

03-Gateway_Ingress/04b-HTTPS-max-TLS-version/VirtualService.yaml

@@ -0,0 +1,20 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld
+            port:
+              number: 80
+      rewrite:
+        uri: "/"

03-Gateway_Ingress/05-TCP-FORWARDING/Deployment.yaml

@@ -1,18 +1,3 @@
-apiVersion: v1
-kind: Service
-metadata:
-  name: helloworld
-  labels:
-    app: helloworld
-    service: helloworld
-spec:
-  ports:
-    - port: 8080
-      name: http
-      targetPort: 80
-  selector:
-    app: helloworld
----
 apiVersion: apps/v1
 kind: Deployment
 metadata:
@@ -31,10 +16,11 @@ spec:
     spec:
       containers:
         - name: helloworld
-          image: nginx
+          image: oriolfilter/https-nginx-demo
           resources:
             requests:
               cpu: "100m"
           imagePullPolicy: IfNotPresent
           ports:
             - containerPort: 80
+            - containerPort: 443

03-Gateway_Ingress/05-TCP-FORWARDING/Gateway.yaml

@@ -0,0 +1,20 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway
+  servers:
+    - port:
+        number: 80
+        name: tcp-1
+        protocol: TCP
+      hosts:
+        - "*"
+    - port:
+        number: 443
+        name: tcp-2
+        protocol: TCP
+      hosts:
+        - "*"

03-Gateway_Ingress/05-TCP-FORWARDING/README.md

@@ -5,7 +5,7 @@ include_toc: true
 
 # Based on
 
-- [08a-HTTPS-min-TLS-version](../08a-HTTPS-min-TLS-version)
+- [04a-HTTPS-min-TLS-version](../04a-HTTPS-min-TLS-version)
 
 # Description
 
@@ -18,7 +18,7 @@ The same backend also contains the same service but running as HTTP, and for suc
 Additionally, the backend used, has HTTP2 enable, which also will be used to confirm that it's working as intended.
 
 > **Note:**\
-> For more information about the image used refer to [here](https://hub.docker.com/r/oriolfilter/https-apache-demo)
+> For more information about the image used refer to [here](https://hub.docker.com/r/oriolfilter/https-nginx-demo)
 
 # Configuration
 
@@ -84,7 +84,7 @@ spec:
 
 ## Service
 
-The service will forward incoming traffic from the service port 8443, that will be forwarded towards the port 443 from the deployment.
+The service will forward incoming traffic from the service port `8443`, that will be forwarded towards the port `443` from the deployment.
 
 
 ```yaml
@@ -111,7 +111,7 @@ spec:
 Deployment listens to port 80 and 443.
 
 > **Note:**\
-> For more information about the image used refer to [here](https://hub.docker.com/r/oriolfilter/https-apache-demo)
+> For more information about the image used refer to [here](https://hub.docker.com/r/oriolfilter/https-nginx-demo)
 
 ```yaml
 apiVersion: apps/v1

03-Gateway_Ingress/05-TCP-FORWARDING/Service.yaml

@@ -0,0 +1,19 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 8080
+      name: http-web
+      targetPort: 80
+      protocol: TCP
+    - port: 8443
+      name: https-web
+      targetPort: 443
+      protocol: TCP
+  selector:
+    app: helloworld

03-Gateway_Ingress/05-TCP-FORWARDING/VirtualService.yaml

@@ -1,25 +1,4 @@
 apiVersion: networking.istio.io/v1alpha3
-kind: Gateway
-metadata:
-  name: helloworld-gateway
-spec:
-  selector:
-    istio: ingressgateway
-  servers:
-    - port:
-        number: 80
-        name: tcp-1
-        protocol: TCP
-      hosts:
-        - "*"
-    - port:
-        number: 443
-        name: tcp-2
-        protocol: TCP
-      hosts:
-        - "*"
----
-apiVersion: networking.istio.io/v1alpha3
 kind: VirtualService
 metadata:
   name: helloworld-vs

03-Gateway_Ingress/06-TLS-PASSTHROUGH/Deployment.yaml

@@ -0,0 +1,26 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-nginx
+  labels:
+    app: helloworld
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+  template:
+    metadata:
+      labels:
+        app: helloworld
+    spec:
+      containers:
+        - name: helloworld
+          image: oriolfilter/https-nginx-demo
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: Always #Always
+          ports:
+            - containerPort: 80
+            - containerPort: 443

03-Gateway_Ingress/06-TLS-PASSTHROUGH/Gateway.yaml

@@ -0,0 +1,17 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+  namespace: default
+spec:
+  selector:
+    istio: ingressgateway
+  servers:
+    - port:
+        number: 443
+        name: https-web
+        protocol: HTTPS
+      hosts:
+        - "*"
+      tls:
+        mode: PASSTHROUGH

03-Gateway_Ingress/06-TLS-PASSTHROUGH/README.md

@@ -5,7 +5,7 @@ include_toc: true
 
 # Based on
 
-- [10-TCP-FORWARDING](../10-TCP-FORWARDING)
+- [05-TCP-FORWARDING](../05-TCP-FORWARDING)
 
 # Description
 
@@ -14,7 +14,7 @@ The previous example was modified set TLS Forwarding for the HTTPS, meaning that
 This requires a deployment with a service HTTPS (as it will need to handle the TLS termination ...). 
 
 > **Note:**\
-> For more information about the image used refer to [here](https://hub.docker.com/r/oriolfilter/https-apache-demo)
+> For more information about the image used refer to [here](https://hub.docker.com/r/oriolfilter/https-nginx-demo)
 
 # Configuration
 
@@ -104,7 +104,7 @@ spec:
 Deployment listens to port 80 and 443.
 
 > **Note:**\
-> For more information about the image used refer to [here](https://hub.docker.com/r/oriolfilter/https-apache-demo)
+> For more information about the image used refer to [here](https://hub.docker.com/r/oriolfilter/https-nginx-demo)
 
 ```yaml
 apiVersion: apps/v1
@@ -160,6 +160,7 @@ kubectl get svc -l istio=ingressgateway -A
 NAME                   TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)                                      AGE
 istio-ingressgateway   LoadBalancer   10.97.47.216   192.168.1.50   15021:31316/TCP,80:32012/TCP,443:32486/TCP   39h
 ```
+
 ### curl HTTPS
 
 Well, it just works.

03-Gateway_Ingress/06-TLS-PASSTHROUGH/Service.yaml

@@ -0,0 +1,16 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - name: https
+      port: 8443
+      targetPort: 443
+      protocol: TCP
+      appProtocol: HTTPS
+  selector:
+    app: helloworld

03-Gateway_Ingress/06-TLS-PASSTHROUGH/VirtualService.yaml

@@ -1,22 +1,4 @@
 apiVersion: networking.istio.io/v1alpha3
-kind: Gateway
-metadata:
-  name: helloworld-gateway
-  namespace: default
-spec:
-  selector:
-    istio: ingressgateway
-  servers:
-    - port:
-        number: 443
-        name: https-web
-        protocol: HTTPS
-      hosts:
-        - "*"
-      tls:
-        mode: PASSTHROUGH
----
-apiVersion: networking.istio.io/v1alpha3
 kind: VirtualService
 metadata:
   name: helloworld-vs

03-Gateway_Ingress/07-HTTP-to-HTTPS-traffic-redirect/Gateway.yaml

@@ -0,0 +1,25 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"
+      tls:
+        httpsRedirect: true
+    - port:
+        number: 443
+        name: https-web
+        protocol: HTTPS
+      hosts:
+        - "*"
+      tls:
+        mode: SIMPLE
+        credentialName: my-tls-cert-secret

03-Gateway_Ingress/07-HTTP-to-HTTPS-traffic-redirect/README.md

@@ -0,0 +1,218 @@
+---
+gitea: none
+include_toc: true
+---
+
+# Based on
+
+- [03-HTTPS-Gateway-Simple-TLS](../03-HTTPS-Gateway-Simple-TLS)
+
+# Description
+
+This example adds `HTTP` to `HTTPS` redirect at the port `80` of the gateway, which listens for HTTP traffic.
+
+Also contains a listens for `HTTPS` traffic at the port 443, with a self-signed certificate. This will be used to ensure that the redirect is working correctly.
+
+
+> **NOTE:**\
+> This example is kept at minimal, without the need of containing a `Virtual Service`, a `Service` nor a `Deployment/Pod`.
+
+# Configuration applied
+
+## Gateway
+
+The port `80` listens for any host, expecting `HTTP` traffic.\
+As `tls.httpsRedirect` is set to `true`, the incoming traffic will be redirected to `HTTPS`, effectively enabling the `HTTP` to `HTTPS` redirect.
+
+
+The port `443` is expecting traffic that use the `HTTPS` protocol, without being limited to specific hosts.\
+The TLS configuration is set to simple, and the credentials (the object that contains the certificates/TLS configuration) is set to `my-tls-cert-secret`.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"
+      tls:
+        httpsRedirect: true
+    - port:
+        number: 443
+        name: https-web
+        protocol: HTTPS
+      hosts:
+        - "*"
+      tls:
+        mode: SIMPLE
+        credentialName: my-tls-cert-secret
+```
+
+> **Note:**\
+> The credentials resource is created further bellow through the [Walkthrough](#walkthrough) steps.
+
+> **Note:**\
+> For more information regarding the TLS mode configuration, refer to the following [Istio documentation regarding the TLS mode field](https://istio.io/latest/docs/reference/config/networking/gateway/#ServerTLSSettings-TLSmode).
+
+# Walkthrough
+
+## Generate client and server certificate and key files
+
+First step will be to generate the certificate and key files to be able to set them to the Gateway resource.
+
+### Create a folder to store files.
+
+Create the folder to contain the files that will be generated. 
+
+```shell
+mkdir certfolder
+```
+
+### Create a certificate and a private key.
+
+```shell
+openssl req -x509 -sha256 -nodes -days 365 -subj '/O=Internet of things/CN=lb.net' -newkey rsa:2048 -keyout certfolder/istio.cert.key -out certfolder/istio.cert.crt
+```
+
+The files generated are the following:
+
+```yaml
+private-key: certfolder/istio.cert.key
+root-certificate: certfolder/istio.cert.crt
+```
+
+The information set to the certificate generated is the following:
+
+```yaml
+Organization-name: Internet of things
+CN: lb.net
+```
+
+### Create a TLS secret
+
+At this step we create the tls secret `my-tls-cert-secret` on the namespace `istio-system`.
+
+```shell
+kubectl create -n istio-system secret tls my-tls-cert-secret \
+  --key=certfolder/istio.cert.key \
+  --cert=certfolder/istio.cert.crt
+```
+```text
+secret/my-tls-cert-secret created
+```
+```text
+service/helloworld created
+deployment.apps/helloworld-nginx created
+gateway.networking.istio.io/helloworld-gateway created
+virtualservice.networking.istio.io/helloworld-vs created
+```
+
+> **Note:**\
+> It's Important that the secret is located in the same namespace as the Load Balancer used. In my case is the `istio-system`, but it will vary based on the environment.
+
+
+## Deploy resources
+
+```shell
+kubectl apply -f ./
+```
+```text
+gateway.networking.istio.io/helloworld-gateway created
+```
+
+## Test the service
+
+### Get LB IP
+
+```shell
+kubectl get svc -l istio=ingressgateway -A
+```
+```text
+NAME                   TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)                                      AGE
+istio-ingressgateway   LoadBalancer   10.97.47.216   192.168.1.50   15021:31316/TCP,80:32012/TCP,443:32486/TCP   39h
+```
+
+### Curl --HEAD
+
+We receive the status message `301 Moved Permanently`.
+
+This points that we are being redirected somewhere. By default, `curl` doesn't follow the redirects. 
+
+To confirm the redirect is being performed towards the `HTTPS` service, we allow `curl` to follow redirects.
+
+```shell
+curl  http://192.168.1.50 -I
+```
+```text
+HTTP/1.1 301 Moved Permanently
+location: https://192.168.1.50/
+date: Tue, 25 Apr 2023 23:59:34 GMT
+server: istio-envoy
+transfer-encoding: chunked
+```
+
+### Curl --HEAD follow redirects
+
+Allowing `curl` to follow redirects, we notice the following output:
+
+- First we receive the same message from before, as we connected to the same service.
+
+- Afterwards we are met with a status code `404`, which is expected as we don't have any service configured behind this gateway.
+
+> **NOTE:**\
+> Due using a self-signed certificate, had to allow accessing "insecure" `HTTPS` destinations.  
+
+```shell
+curl  http://192.168.1.50 -I -L -k
+```
+```text
+HTTP/1.1 301 Moved Permanently
+location: https://192.168.1.50/
+date: Wed, 26 Apr 2023 00:05:24 GMT
+server: istio-envoy
+transfer-encoding: chunked
+
+HTTP/2 404 
+date: Wed, 26 Apr 2023 00:05:24 GMT
+server: istio-envoy
+```
+
+## Cleanup
+
+```shell
+kubectl delete -n istio-system secret my-tls-cert-secret
+```
+
+```text
+secret "my-tls-cert-secret" deleted
+```
+
+```shell
+kubectl delete -f ./
+```
+```text
+gateway.networking.istio.io "helloworld-gateway" deleted
+```
+
+```shell
+rm -rv certfolder/
+```
+
+```text
+removed 'certfolder/istio.cert.key'
+removed 'certfolder/istio.cert.crt'
+removed directory 'certfolder/'
+```
+
+# Links of Interest
+
+
+- https://istio.io/latest/docs/reference/config/networking/gateway/#ServerTLSSettings

03-Gateway_Ingress/README.md

@@ -0,0 +1,12 @@
+# Description
+
+This section focuses (but not limited to) on the configuration of `gateway` objects, providing examples of instances regarding how to limit to which `VirtualService` objects a `Gateway` object can connect to, regarding how to configure a HTTP to HTTPS redirect, or it's TLS configuration. 
+
+# Examples
+
+- 01-header_routing
+- 02-DirectResponse-HTTP-Body
+- 03-HTTPRewrite
+- 04-HTTPRedirect
+
+

04-Backends/01-Service_Entry/Gateway.yaml

@@ -0,0 +1,14 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"

04-Backends/01-Service_Entry/README.md

@@ -0,0 +1,205 @@
+# Description
+
+This example uses a resource `ServiceEntry` to "integrate" external resources into our `Istio Service Mesh`.
+
+It also explores the different behaviors between specifying the destination URL on the headers or not.
+
+The following page has been used for testing purposes:
+
+- info.cern.ch
+
+> **Quick disclaimer**:\
+> I have no relation with that page.
+
+# Configuration
+
+## ServiceEntry
+
+This `ServiceEntry` resource, defines as a destination the URL `info.cern.ch`.
+
+Note that location is set to `MESH_EXTERNAL` and that the resolution is set to `DNS`, this means that the resource is external to ou `Istio Service Mesh`, and the URL will be resolved through `DNS`
+
+Bear in mind that when Istio is communicating with resources externals to the mesh, `mTLS` is disabled.
+
+Also, policy enforcement is performed in the client side instead of the server side.
+
+> **Note:**/
+> For more information regarding the `resolution` field or the `location` field, refer to the following official Istio documentations:\
+> - [ServiceEntry.Location](https://istio.io/latest/docs/reference/config/networking/service-entry/#ServiceEntry-Location)\
+> - [ServiceEntry.Resolution](https://istio.io/latest/docs/reference/config/networking/service-entry/#ServiceEntry-Resolution)
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: ServiceEntry
+metadata:
+  name: external-cern-service
+spec:
+  hosts:
+    - info.cern.ch
+  ports:
+    - number: 80
+      name: http
+      protocol: HTTP
+  resolution: DNS
+  location: MESH_EXTERNAL
+```
+
+## Gateway
+
+Listens for `HTTP` traffic at the port `80` without limiting to any host.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"
+```
+
+
+## VirtualService
+
+There has been configured 2 paths:
+
+- "/external"
+- "/external-noh"
+
+Both routes will forward the request towards the destination URL `info.cern.ch`.
+
+Highlight that the destination is `info.cern.ch`, which is the same as the contents set on the field `host` from the [ServiceEntry resource configured above](#serviceentry).
+
+The difference between `/external` and `/external-noh` is that the first path will contain a header named `HOST`, with the contents set to `info.cern.ch`, it being the URL from the external service.
+
+On the [Walkthrough](#walkthrough) section we will observe the different behaviors of these paths, being the only difference the header attributed.
+
+Also, we have set a timeout of 3 seconds towards the external services.
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - name: http-external-service
+      timeout: 3s
+      match:
+        - uri:
+            exact: "/external"
+      route:
+        - destination:
+            host: info.cern.ch
+            port:
+              number: 80
+      rewrite:
+        uri: "/"
+      headers:
+        request:
+          set:
+            HOST: "info.cern.ch"
+
+    - name: https-external-service-without-headers
+      timeout: 3s
+      match:
+        - uri:
+            exact: "/external-noh"
+      route:
+        - destination:
+            host: info.cern.ch
+            port:
+              number: 80
+      rewrite:
+        uri: "/"
+```
+
+# Walkthrough
+
+## Deploy the resources
+
+```shell
+kubectl apply -f ./
+```
+```text
+serviceentry.networking.istio.io/external-cern-service created
+gateway.networking.istio.io/helloworld-gateway created
+virtualservice.networking.istio.io/helloworld-vs created
+```
+
+## Test the service
+
+### Get LB IP
+
+```shell
+kubectl get svc -l istio=ingressgateway -A
+```
+```text
+NAME                   TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)                                      AGE
+istio-ingressgateway   LoadBalancer   10.97.47.216   192.168.1.50   15021:31316/TCP,80:32012/TCP,443:32486/TCP   39h
+```
+
+### /external
+
+We can visualize the page contents without issues, nothing to highlight.
+
+```shell
+curl 192.168.1.50/external
+```
+```text
+<html><head></head><body><header>
+<title>http://info.cern.ch</title>
+</header>
+
+<h1>http://info.cern.ch - home of the first website</h1>
+<p>From here you can:</p>
+<ul>
+<li><a href="http://info.cern.ch/hypertext/WWW/TheProject.html">Browse the first website</a></li>
+<li><a href="http://line-mode.cern.ch/www/hypertext/WWW/TheProject.html">Browse the first website using the line-mode browser simulator</a></li>
+<li><a href="http://home.web.cern.ch/topics/birth-web">Learn about the birth of the web</a></li>
+<li><a href="http://home.web.cern.ch/about">Learn about CERN, the physics laboratory where the web was born</a></li>
+</ul>
+</body></html>
+```
+
+### /external-noh
+
+We don't receive any output.
+
+Even if we resolve the destination IP for the URL `info.cern.ch`, the destination might have a **Reverse Proxy** or any other ingress resource that could condition handling this request.
+
+Due to the `HOST` field not being modified after we set the request, it might not be able to pass the filtering rules set on the destination server, on this scenario being the service responsible for receiving requests with the URL `info.cern.ch`.
+
+```shell
+curl 192.168.1.50/external-noh
+```
+```text
+</pre></body></html>
+```
+
+## Cleanup
+
+```shell
+kubectl delete -f ./
+```
+```text
+serviceentry.networking.istio.io "external-cern-service" deleted
+gateway.networking.istio.io "helloworld-gateway" deleted
+virtualservice.networking.istio.io "helloworld-vs" deleted
+```
+
+# Links of interest:
+
+- https://istio.io/latest/docs/reference/config/networking/service-entry/#ServiceEntry-Location
+

04-Backends/01-Service_Entry/ServiceEntry.yaml

@@ -0,0 +1,13 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: ServiceEntry
+metadata:
+  name: external-cern-service
+spec:
+  hosts:
+    - info.cern.ch
+  ports:
+    - number: 80
+      name: http
+      protocol: HTTP
+  resolution: DNS
+  location: MESH_EXTERNAL

04-Backends/01-Service_Entry/VirtualService.yaml

@@ -0,0 +1,39 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - name: http-external-service
+      timeout: 3s
+      match:
+        - uri:
+            exact: "/external"
+      route:
+        - destination:
+            host: info.cern.ch
+            port:
+              number: 80
+      rewrite:
+        uri: "/"
+      headers:
+        request:
+          set:
+            HOST: "info.cern.ch"
+
+    - name: https-external-service-without-headers
+      timeout: 3s
+      match:
+        - uri:
+            exact: "/external-noh"
+      route:
+        - destination:
+            host: info.cern.ch
+            port:
+              number: 80
+      rewrite:
+        uri: "/"

04-Backends/02-Outboud-Traffic-Policy/Deployment.yaml

@@ -0,0 +1,25 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-nginx
+  labels:
+    app: helloworld
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+  template:
+    metadata:
+      labels:
+        app: helloworld
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent #Always
+          ports:
+            - containerPort: 80

04-Backends/02-Outboud-Traffic-Policy/Gateway.yaml

@@ -0,0 +1,14 @@
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway # use istio default controller
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"

04-Backends/02-Outboud-Traffic-Policy/README.md

@@ -0,0 +1,338 @@
+---
+gitea: none
+include_toc: true
+---
+
+# Description
+
+Based on the previous example where we configured an external service through a `ServiceEntry` object, this example compares the behavior between setting up the MeshConfig `OutboundTrafficPolicy.mode` setting to `REGISTRY_ONLY` and `ALLOW_ANY`.
+
+- ALLOW_ANY: Allows all egress/outbound traffic from the mesh.
+
+- REGISTRY_ONLY: Restricted to services that figure in the service registry a and the ServiceEntry objects.
+
+More info regarding this configuration at the pertinent documentation (https://istio.io/latest/docs/reference/config/istio.mesh.v1alpha1/#MeshConfig-OutboundTrafficPolicy-Mode)
+
+> **Note:**\
+> For more information about the image used refer to [here](https://hub.docker.com/r/oriolfilter/https-nginx-demo)
+
+# Based on
+
+- [01-Service_Entry](../01-Service_Entry)
+
+# Configuration
+
+## Gateway
+
+Deploys an Istio gateway that's listening to the port `80` for `HTTP` traffic.
+
+It doesn't filter for any specific host.
+
+The `selector` field is used to "choose" which Istio Load Balancers will have this gateway assigned to.
+
+The Istio `default` profile creates a Load Balancer in the namespace `istio-system` that has the label `istio: ingressgateway` set, allowing us to target that specific Load Balancer and assign this gateway resource to it.
+
+```shell
+apiVersion: networking.istio.io/v1alpha3
+kind: Gateway
+metadata:
+  name: helloworld-gateway
+spec:
+  selector:
+    istio: ingressgateway
+  servers:
+    - port:
+        number: 80
+        name: http
+        protocol: HTTP
+      hosts:
+        - "*"
+```
+
+> **Note:**\
+> The credentials resource is created further bellow through the [Walkthrough](#walkthrough) steps.
+
+> **Note:**\
+> For more information regarding the TLS mode configuration, refer to the following [Istio documentation regarding the TLS mode field](https://istio.io/latest/docs/reference/config/networking/gateway/#ServerTLSSettings-TLSmode).
+
+## VirtualService
+
+This configuration hosts 2 backends, 1 being the deployed service `helloworld.default.svc.cluster.local`, which will be accessible through the URL path `/helloworld`.
+
+The second service will be accessible through the URL path `/external`, and will use as a backend the deployed `ServiceEntry` object, as well it has a timeout setting of 3 seconds.
+
+This destination is the service that contains the `HTTPS` deployment, running over the port `8443`
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: VirtualService
+metadata:
+  name: helloworld-vs
+spec:
+  hosts:
+    - "*"
+  gateways:
+    - helloworld-gateway
+  http:
+    - match:
+        - uri:
+            exact: /helloworld
+      route:
+        - destination:
+            host: helloworld
+            port:
+              number: 80
+      rewrite:
+        uri: "/"
+
+    - timeout: 3s
+      match:
+        - uri:
+            exact: "/external"
+      route:
+        - destination:
+            host: help.websiteos.com
+            port:
+              number: 80
+      rewrite:
+        uri: "/websiteos/example_of_a_simple_html_page.htm"
+      headers:
+        request:
+          set:
+            HOST: "help.websiteos.com"
+```
+
+## Service
+
+The service will forward incoming HTTP TCP traffic from the port `80`, towards the deployment port `80`.
+
+```yaml
+apiVersion: v1
+kind: Service
+metadata:
+  name: helloworld
+  labels:
+    app: helloworld
+    service: helloworld
+spec:
+  ports:
+    - port: 80
+      name: http
+  selector:
+    app: helloworld
+```
+
+## Deployment
+
+Nginx deployment listens to port 80.
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: helloworld-nginx
+  labels:
+    app: helloworld
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: helloworld
+  template:
+    metadata:
+      labels:
+        app: helloworld
+    spec:
+      containers:
+        - name: helloworld
+          image: nginx
+          resources:
+            requests:
+              cpu: "100m"
+          imagePullPolicy: IfNotPresent #Always
+          ports:
+            - containerPort: 80
+```
+
+### ServiceEntry
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: ServiceEntry
+metadata:
+  name: external-svc
+spec:
+  hosts:
+    - help.websiteos.com
+  ports:
+    - number: 80
+      name: http
+      protocol: HTTP
+  resolution: DNS
+  location: MESH_EXTERNAL
+```
+
+## ServiceEntry
+
+This `ServiceEntry` resource, defines as a destination the URL `help.websiteos.com`.
+
+Note that location is set to `MESH_EXTERNAL` and that the resolution is set to `DNS`, this means that the resource is external to ou `Istio Service Mesh`, and the URL will be resolved through `DNS`
+
+Bear in mind that when Istio is communicating with resources externals to the mesh, `mTLS` is disabled.
+
+Also, policy enforcement is performed in the client side instead of the server side.
+
+> **Note:**/
+> For more information regarding the `resolution` field or the `location` field, refer to the following official Istio documentations:\
+> - [ServiceEntry.Location](https://istio.io/latest/docs/reference/config/networking/service-entry/#ServiceEntry-Location)\
+> - [ServiceEntry.Resolution](https://istio.io/latest/docs/reference/config/networking/service-entry/#ServiceEntry-Resolution)
+
+```yaml
+apiVersion: networking.istio.io/v1alpha3
+kind: ServiceEntry
+metadata:
+  name: external-svc
+spec:
+  hosts:
+    - help.websiteos.com
+  ports:
+    - number: 80
+      name: http
+      protocol: HTTP
+  resolution: DNS
+  location: MESH_EXTERNAL
+```
+
+
+# Walkthrough
+
+## Set ALLOW_ANY outbound traffic policy
+
+First step will be to have the cluster with the `meshConfig.outboundTrafficPolicy.mode` setting set to `ALLOW_ANY`.
+
+In case you are not using a "free to destroy" sandbox, you should update the setting through the `IstioOperator` object.
+
+```shell
+istioctl install --set profile=default -y --set meshConfig.accessLogFile=/dev/stdout  --set meshConfig.outboundTrafficPolicy.mode=ALLOW_ANY
+```
+
+## Deploy resources
+
+```shell
+kubectl apply -f ./
+```
+```text
+deployment.apps/helloworld-nginx created
+gateway.networking.istio.io/helloworld-gateway created
+service/helloworld created
+serviceentry.networking.istio.io/external-svc created
+virtualservice.networking.istio.io/helloworld-vs created
+```
+
+## Get LB IP
+
+```shell
+kubectl get svc istio-ingressgateway -n istio-system
+```
+
+```text
+NAME                   TYPE           CLUSTER-IP     EXTERNAL-IP    PORT(S)                                      AGE
+istio-ingressgateway   LoadBalancer   10.97.47.216   192.168.1.50   15021:31316/TCP,80:32012/TCP,443:32486/TCP   39h
+```
+
+## Test deployments
+
+```shell
+curl 192.168.1.50/helloworld -I
+```
+
+```text
+HTTP/1.1 200 OK
+server: istio-envoy
+date: Sat, 14 Oct 2023 10:53:45 GMT
+content-type: text/html
+content-length: 615
+last-modified: Tue, 15 Aug 2023 17:03:04 GMT
+etag: "64dbafc8-267"
+accept-ranges: bytes
+x-envoy-upstream-service-time: 53
+```
+
+```shell
+curl 192.168.1.50/external -I
+```
+
+```text
+HTTP/1.1 200 OK
+date: Sat, 14 Oct 2023 10:54:13 GMT
+content-type: text/html
+content-length: 5186
+last-modified: Mon, 17 Mar 2014 17:25:03 GMT
+expires: Thu, 31 Dec 2037 23:55:55 GMT
+cache-control: max-age=315360000
+x-envoy-upstream-service-time: 306
+server: istio-envoy
+```
+
+
+## Test egress the helloworld deployment
+
+It returns a 301 code, meaning that it was able to reach the destination, and it was attempted to redirect the traffic from HTTP to HTTPS.
+
+```shell
+kubectl exec -i -t "$(kubectl get pod -l app=helloworld | tail -n 1 | awk '{print $1}')" -- curl wikipedia.com -I
+```
+
+```text
+HTTP/1.1 301 Moved Permanently
+server: envoy
+date: Sat, 14 Oct 2023 10:54:34 GMT
+content-type: text/html
+content-length: 169
+location: https://wikipedia.com/
+x-envoy-upstream-service-time: 61
+```
+
+## Set REGISTRY_ONLY outbound traffic policy
+
+```shell
+istioctl install --set profile=default -y --set meshConfig.accessLogFile=/dev/stdout  --set meshConfig.outboundTrafficPolicy.mode=REGISTRY_ONLY
+```
+
+In case you are not using a "free to destroy" sandbox, you should update the setting through the `IstioOperator` object.
+
+## Test (again) egress the helloworld deployment
+
+It returns a 502 code, meaning that it wasn't able to reach the destination.
+
+```shell
+kubectl exec -i -t "$(kubectl get pod -l app=helloworld | tail -n 1 | awk '{print $1}')" -- curl wikipedia.com -I
+```
+
+```text
+HTTP/1.1 502 Bad Gateway
+date: Thu, 20 Apr 2023 18:08:37 GMT
+server: envoy
+transfer-encoding: chunked
+```
+
+This allowed us to confirm how the setting `outboundTrafficPolicy.mode` influences the reachability of the traffic.
+
+## Cleanup
+
+```shell
+kubectl delete -f ./
+```
+```text
+deployment.apps "helloworld-nginx" deleted
+gateway.networking.istio.io "helloworld-gateway" deleted
+service "helloworld" deleted
+serviceentry.networking.istio.io "external-svc" deleted
+virtualservice.networking.istio.io "helloworld-vs" deleted
+```
+
+# Links of Interest
+
+- https://istio.io/latest/docs/tasks/traffic-management/egress/egress-control/#controlled-access-to-external-services
+
+- https://istio.io/latest/docs/tasks/traffic-management/egress/egress-control/#envoy-passthrough-to-external-services