CKA 試験問題を無料オンラインアクセス

Task Summary
* SSH into cka000060
* Add the Argo CD Helm repo named argo
* Generate a manifest (~/argo-helm.yaml) for Argo CD version 7.7.3
* Target namespace: argocd
* Do not install CRDs
* Just generate, don't install
# Step-by-Step Solution
1## SSH into the correct host
ssh cka000060
## Required - skipping this = zero score
2## Add the Argo CD Helm repository
helm repo add argo https://argoproj.github.io/argo-helm
helm repo update
# This adds the official Argo Helm chart source.
3## Generate Argo CD Helm chart template (version 7.7.3)
Use the helm template command to generate a manifest and write it to ~/argo-helm.yaml.
helm template argocd argo/argo-cd \
--version 7.7.3 \
--namespace argocd \
--set crds.install=false \
> ~/argo-helm.yaml
* argocd # Release name (can be anything; here it's same as the namespace)
* --set crds.install=false # Disables CRD installation
* > ~/argo-helm.yaml # Save to required file
# 4## Verify the generated file (optional but smart)
head ~/argo-helm.yaml
Check that it contains valid Kubernetes YAML and does not include CRDs.
# Final Command Summary
ssh cka000060
helm repo add argo https://argoproj.github.io/argo-helm
helm repo update
helm template argocd argo/argo-cd \
--version 7.7.3 \
--namespace argocd \
--set crds.install=false \
> ~/argo-helm.yaml
head ~/argo-helm.yaml # Optional verification

Persistent Volume
A persistent volume is a piece of storage in a Kubernetes cluster. PersistentVolumes are a cluster-level resource like nodes, which don't belong to any namespace. It is provisioned by the administrator and has a particular file size. This way, a developer deploying their app on Kubernetes need not know the underlying infrastructure. When the developer needs a certain amount of persistent storage for their application, the system administrator configures the cluster so that they consume the PersistentVolume provisioned in an easy way.
Creating Persistent Volume
kind: PersistentVolume
apiVersion: v1
metadata:
name:app-data
spec:
capacity: # defines the capacity of PV we are creating
storage: 2Gi #the amount of storage we are tying to claim
accessModes: # defines the rights of the volume we are creating
- ReadWriteMany
hostPath:
path: "/srv/app-data" # path to which we are creating the volume
Challenge
* Create a Persistent Volume named app-data, with access mode ReadWriteMany, storage classname shared, 2Gi of storage capacity and the host path /srv/app-data.

2. Save the file and create the persistent volume.
Image for post

3. View the persistent volume.

* Our persistent volume status is available meaning it is available and it has not been mounted yet. This status will change when we mount the persistentVolume to a persistentVolumeClaim.
PersistentVolumeClaim
In a real ecosystem, a system admin will create the PersistentVolume then a developer will create a PersistentVolumeClaim which will be referenced in a pod. A PersistentVolumeClaim is created by specifying the minimum size and the access mode they require from the persistentVolume.
Challenge
* Create a Persistent Volume Claim that requests the Persistent Volume we had created above. The claim should request 2Gi. Ensure that the Persistent Volume Claim has the same storageClassName as the persistentVolume you had previously created.
kind: PersistentVolume
apiVersion: v1
metadata:
name:app-data
spec:
accessModes:
- ReadWriteMany
resources:
requests:
storage: 2Gi
storageClassName: shared
2. Save and create the pvc
njerry191@cloudshell:~ (extreme-clone-2654111)$ kubect1 create -f app-data.yaml persistentvolumeclaim/app-data created
3. View the pvc
Image for post

4. Let's see what has changed in the pv we had initially created.
Image for post

Our status has now changed from available to bound.
5. Create a new pod named myapp with image nginx that will be used to Mount the Persistent Volume Claim with the path /var/app/config.
Mounting a Claim
apiVersion: v1
kind: Pod
metadata:
creationTimestamp: null
name: app-data
spec:
volumes:
- name:congigpvc
persistenVolumeClaim:
claimName: app-data
containers:
- image: nginx
name: app
volumeMounts:
- mountPath: "/srv/app-data "
name: configpvc

Task Summary
* SSH into the correct node: cka000037
* Modify existing deployment synergy-leverager
* Add a sidecar container:
* Name: sidecar
* Image: busybox:stable
* Command:
/bin/sh -c "tail -n+1 -f /var/log/synergy-leverager.log"
* Use a shared volume mounted at /var/log
* Don't touch existing container config except adding volume mount
Step-by-Step Solution
1## SSH into the correct node
ssh cka000037
## Skipping this will result in a zero score.
2## Edit the deployment
kubectl edit deployment synergy-leverager
This opens the deployment YAML in your default editor (vi or similar).
3## Modify the spec as follows
# Inside the spec.template.spec, do these 3 things:
# A. Define a shared volume
Add under volumes: (at the same level as containers):
volumes:
- name: log-volume
emptyDir: {}
# B. Add volume mount to the existing container
Locate the existing container under containers: and add this:
volumeMounts:
- name: log-volume
mountPath: /var/log
# Do not change any other configuration for this container.
# C. Add the sidecar container
Still inside containers:, add the new container definition after the first one:
- name: sidecar
image: busybox:stable
command:
- /bin/sh
- -c
- "tail -n+1 -f /var/log/synergy-leverager.log"
volumeMounts:
- name: log-volume
mountPath: /var/log
spec:
containers:
- name: main-container
image: your-existing-image
volumeMounts:
- name: log-volume
mountPath: /var/log
- name: sidecar
image: busybox:stable
command:
- /bin/sh
- -c
- "tail -n+1 -f /var/log/synergy-leverager.log"
volumeMounts:
- name: log-volume
mountPath: /var/log
volumes:
- name: log-volume
emptyDir: {}
Save and exit
If using vi or vim, type:
bash
CopyEdit
wq
5## Verify
Check the updated pods:
kubectl get pods -l app=synergy-leverager
Pick a pod name and describe it:
kubectl describe pod <pod-name>
Confirm:
* 2 containers running (main-container + sidecar)
* Volume mounted at /var/log
ssh cka000037
kubectl edit deployment synergy-leverager
# Modify as explained above
kubectl get pods -l app=synergy-leverager
kubectl describe pod <pod-name>

Solution:
#vi pv.yaml
apiVersion: v1
kind: PersistentVolume
metadata:
name: app-config
spec:
capacity:
storage: 1Gi
accessModes:
- ReadOnlyMany
hostPath:
path: /srv/app-config
#
kubectl create -f pv.yaml