Update lab4

docs/lab-4.md

@@ -1,6 +1,6 @@
 # Deployment and Networking in Kubernetes
 
-Lab Session 4 - 4 Nov, 2024
+Lab Session 4 - 7 Nov, 2024
 
 # Introduction
 
@@ -14,35 +14,21 @@ To submit the answers to this lab session, please fill in your answers
 in this document in-place. This should be done before the beginning of
 the next course.
 
-## Prerequisite
-
-If you are using the computer of ESIGELEC, the Docker Desktop is
-preinstalled, but you need to enable the Kubernetes feature in Docker
-Desktop’s settings. If you are using your personal computer, please
-download Docker Desktop from the official website of Docker, Inc. and
-enable the Kubernetes feature.
-
-<https://www.docker.com/products/docker-desktop/>
-
-Before starting the lab session, please clear all Kubernetes resources
-from your Kubernetes Cluster by using the button “Reset Kubernetes
-Cluster” in your Docker Desktop (Settings \> Kubernetes).
-
-<!-- I don't add more details because they should already have the software installed. -->
-
 ## Exercise 1 - ReplicaSet
 
 Create a new ReplicaSet with 2 replicas and the Docker image
-`nginx:1.26` and call this resource `nginx`. Use labels `app:nginx`,
-`team=${team}`, and `tier=frontend` for both the ReplicaSet and the
-underlying pods. The pods should expose the container port 80 to receive
-incoming traffic. The name of the container should also be “nginx”.
-Persist the Kubernetes manifest (YAML file) in the Git repository of
-your team under the `k8s` directory.
+`nginx:1.26` and call this resource `nginx`. Use labels
+`school=esigelec`, `app=nginx`, `team=${team}`, and `tier=frontend` for
+both the ReplicaSet and the underlying pods. The pods should expose the
+container port 80 to receive incoming traffic. The name of the container
+should also be “nginx”. Persist the Kubernetes manifest (YAML file) in
+the Git repository of your team under the `k8s` directory as file
+`replicaset-nginx.yaml`.
 
 
 
-    *\[answer: commit to the Git repository of your team\]*
+    *\[answer: optional. Commit code changes directly under the `k8s`
+directory.\]*
 
 
 
@@ -73,24 +59,36 @@ now? Why?
 ## Exercise 2 - Deployment
 
 Create a new Deployment with 2 replicas using the Docker image
-`weekend-server` that you built in the previous lab session and call
-this deployment `weekend-server`. Use labels `app:weekend-server`,
-`team=${team}`, and `tier=backend` for both the Deployment and the
-underlying pods. Persist the Kubernetes manifest (YAML file) in the Git
-repository of your team under the `k8s` directory.
+`mincongclassroom/weekend-server-${team}` that you built in the previous
+lab session and call this deployment `weekend-server`. Use labels
+`school=esigelec`, `app=weekend-server`, `team=${team}`, and
+`tier=backend` for both the Deployment and the underlying pods. Persist
+the Kubernetes manifest (YAML file) in the Git repository of your team
+under the `k8s` directory as file `deployment-weekend-server.yaml`.
+
+In addition to the changes above, please also
+
+- Add environment variable `APP_TEAM` in the manifest to describe your
+  team for the container
+- Add environment variable `APP_AUTHORS` in the manifest to describe
+  yourselves as authors of the container. The format should be
+  “Firstname1 LASTNAME1, Firstname2 LASTNAME2”, such as “Emmanuel
+  MACRON”.
+- Propagate the pod name to the container.
 
 
 
-    *\[answer: commit to the Git repository of your team\]*
+    *\[answer: optional. Commit code changes directly under the `k8s`
+directory.\]*
 
 
 
 
 
 Do you see a ReplicaSet related to your deployment? If yes, write down
 the name of the ReplicaSet, else please share your thoughts. Hint: you
-can use the command `kubectl get` all\` to list all the resources in
-your Kubernetes cluster under the current namespace.
+can use the command `kubectl get all` to list all the resources in your
+Kubernetes cluster under the current namespace.
 
 
 
@@ -110,26 +108,59 @@ Scale up the deployment to 3 replicas and share the command below.
 
 
 
+Upgrade the Docker image of the weekend-server deployment by setting the
+image to another version that you built. Roll out this change and
+observe the status of the Pods, ReplicaSet, and Deployment. Please
+describe your observation here.
+
+
+
+    *\[answer\]*
+
+
+
+
+
+Inspect the revision history of your deployment.
+
+
+
+    *\[answer\]*
+
+
+
+
+
+What if you specify an image that does not exist?
+
+    *\[answer\]*
+
+
+
+
+
 ## Exercise 3 - Service
 
 Provide a networking solution for weekend-server application so that
 this deployment is exposed to other resources inside the Kubernetes
 cluster. Please ensure that access is only granted for resources within
 the Kubernetes cluster, access from external systems is not allowed.
 Persist the Kubernetes manifest (YAML file) in the Git repository of
-your team under the `k8s` directory.
+your team under the `k8s` directory as file
+`service-weekend-server.yaml`.
 
 
 
-    *\[answer: commit to the Git repository of your team\]*
+    *\[answer: optional. Commit code changes directly under the `k8s`
+directory.\]*
 
 
 
 
 
 Port forward to that service by listening to port 8080 of your machine
-and forwarding data to port 80 of the service (`8080:80`) to verify that
-the service is working as expected. Please share the kubectl command.
+and forwarding data to your service weekend-server to verify that the
+service is working as expected. Please share the kubectl command.
 
 
 
@@ -140,15 +171,16 @@ the service is working as expected. Please share the kubectl command.
 
 
 Use another to verify that this is working as expected. Please create a
-helper pod with the image busybox using the command below. Try to use
-different DNS queries to send HTTP requests to the service. Reminder:
-after starting the busybox, you can use `wget` command with output to
-stdout (`-O-`), followed by the URL to make an HTTP request. You can
-exit the pod by pressing CTRL + D (‘D’ stands for disconnect).
+helper pod with the image
+[curlimages/curl](https://hub.docker.com/r/curlimages/curl) using the
+command below. Try to use different DNS queries to send HTTP requests to
+the service. Reminder: after starting the curl image, you can use `curl`
+command followed by the URL to make an HTTP request. You can exit the
+pod by pressing CTRL + D (‘D’ stands for disconnect).
 
 ``` sh
-kubectl run busybox --image=busybox --restart=Never --rm -it -- /bin/sh
-# wget -O- ${URL}
+kubectl run curl-pod --image=curlimages/curl --restart=Never --rm -it -- /bin/sh
+# curl ${URL}
 ```
 
 Here is a reminder of different expressions:
@@ -167,29 +199,3 @@ Please provide the commands and results below.
     *\[answer\]*
 
 
-
-
-
-## Exercise 4 - Upgrade Docker Image
-
-Upgrade the Docker image of the deployment by setting the image to
-`nginx:1.27` and roll out this change. Observe the status of the Pods
-and ReplicaSet. Please describe your observation here.
-
-
-
-    *\[answer\]*
-
-
-
-
-
-Inspect the revision history of your deployment.
-
-
-
-    *\[answer\]*
-
-
-
-