CKA 無料問題集「Linux Foundation Certified Kubernetes Administrator (CKA) Program」
Score:7%
Context
An existing Pod needs to be integrated into the Kubernetes built-in logging architecture (e. g. kubectl logs).
Adding a streaming sidecar container is a good and common way to accomplish this requirement.
Task
Add a sidecar container named sidecar, using the busybox Image, to the existing Pod big-corp-app. The new sidecar container has to run the following command:
/bin/sh -c tail -n+1 -f /va r/log/big-corp-app.log
Use a Volume, mounted at /var/log, to make the log file big-corp-app.log available to the sidecar container.
Context
An existing Pod needs to be integrated into the Kubernetes built-in logging architecture (e. g. kubectl logs).
Adding a streaming sidecar container is a good and common way to accomplish this requirement.
Task
Add a sidecar container named sidecar, using the busybox Image, to the existing Pod big-corp-app. The new sidecar container has to run the following command:
/bin/sh -c tail -n+1 -f /va r/log/big-corp-app.log
Use a Volume, mounted at /var/log, to make the log file big-corp-app.log available to the sidecar container.
正解：
Solution:
#
kubectl get pod big-corp-app -o yaml
#
apiVersion: v1
kind: Pod
metadata:
name: big-corp-app
spec:
containers:
- name: big-corp-app
image: busybox
args:
- /bin/sh
- -c
- >
i=0;
while true;
do
echo "$(date) INFO $i" >> /var/log/big-corp-app.log;
i=$((i+1));
sleep 1;
done
volumeMounts:
- name: logs
mountPath: /var/log
- name: count-log-1
image: busybox
args: [/bin/sh, -c, 'tail -n+1 -f /var/log/big-corp-app.log']
volumeMounts:
- name: logs
mountPath: /var/log
volumes:
- name: logs
emptyDir: {
}
#
kubectl logs big-corp-app -c count-log-1
#
kubectl get pod big-corp-app -o yaml
#
apiVersion: v1
kind: Pod
metadata:
name: big-corp-app
spec:
containers:
- name: big-corp-app
image: busybox
args:
- /bin/sh
- -c
- >
i=0;
while true;
do
echo "$(date) INFO $i" >> /var/log/big-corp-app.log;
i=$((i+1));
sleep 1;
done
volumeMounts:
- name: logs
mountPath: /var/log
- name: count-log-1
image: busybox
args: [/bin/sh, -c, 'tail -n+1 -f /var/log/big-corp-app.log']
volumeMounts:
- name: logs
mountPath: /var/log
volumes:
- name: logs
emptyDir: {
}
#
kubectl logs big-corp-app -c count-log-1
Create a nginx pod with label env=test in engineering namespace
正解：
kubectl run nginx --image=nginx --restart=Never --labels=env=test --namespace=engineering --dry-run -o yaml > nginx-pod.yaml kubectl run nginx --image=nginx --restart=Never --labels=env=test --namespace=engineering --dry-run -o yaml | kubectl create -n engineering -f - YAML File:
apiVersion: v1
kind: Pod
metadata:
name: nginx
namespace: engineering
labels:
env: test
spec:
containers:
- name: nginx
image: nginx
imagePullPolicy: IfNotPresent
restartPolicy: Never
kubectl create -f nginx-pod.yaml
apiVersion: v1
kind: Pod
metadata:
name: nginx
namespace: engineering
labels:
env: test
spec:
containers:
- name: nginx
image: nginx
imagePullPolicy: IfNotPresent
restartPolicy: Never
kubectl create -f nginx-pod.yaml
Create a busybox pod and add "sleep 3600" command
正解：
kubectl run busybox --image=busybox --restart=Never -- /bin/sh -c
"sleep 3600"
"sleep 3600"
Score: 7%
Task
Given an existing Kubernetes cluster running version 1.20.0, upgrade all of the Kubernetes control plane and node components on the master node only to version 1.20.1.
Be sure to drain the master node before upgrading it and uncordon it after the upgrade.
You are also expected to upgrade kubelet and kubectl on the master node.
Task
Given an existing Kubernetes cluster running version 1.20.0, upgrade all of the Kubernetes control plane and node components on the master node only to version 1.20.1.
Be sure to drain the master node before upgrading it and uncordon it after the upgrade.
You are also expected to upgrade kubelet and kubectl on the master node.
正解：
SOLUTION:
[student@node-1] > ssh ek8s
kubectl cordon k8s-master
kubectl drain k8s-master --delete-local-data --ignore-daemonsets --force apt-get install kubeadm=1.20.1-00 kubelet=1.20.1-00 kubectl=1.20.1-00 --disableexcludes=kubernetes kubeadm upgrade apply 1.20.1 --etcd-upgrade=false systemctl daemon-reload systemctl restart kubelet kubectl uncordon k8s-master
[student@node-1] > ssh ek8s
kubectl cordon k8s-master
kubectl drain k8s-master --delete-local-data --ignore-daemonsets --force apt-get install kubeadm=1.20.1-00 kubelet=1.20.1-00 kubectl=1.20.1-00 --disableexcludes=kubernetes kubeadm upgrade apply 1.20.1 --etcd-upgrade=false systemctl daemon-reload systemctl restart kubelet kubectl uncordon k8s-master
List the nginx pod with custom columns POD_NAME and POD_STATUS
正解：
kubectl get po -o=custom-columns="POD_NAME:.metadata.name,
POD_STATUS:.status.containerStatuses[].state"
POD_STATUS:.status.containerStatuses[].state"
Given a partially-functioning Kubernetes cluster, identify symptoms of failure on the cluster.
Determine the node, the failing service, and take actions to bring up the failed service and restore the health of the cluster. Ensure that any changes are made permanently.
You can ssh to the relevant I nodes (bk8s-master-0 or bk8s-node-0) using:
[student@node-1] $ ssh <nodename>
You can assume elevated privileges on any node in the cluster with the following command:
[student@nodename] $ | sudo -i
Determine the node, the failing service, and take actions to bring up the failed service and restore the health of the cluster. Ensure that any changes are made permanently.
You can ssh to the relevant I nodes (bk8s-master-0 or bk8s-node-0) using:
[student@node-1] $ ssh <nodename>
You can assume elevated privileges on any node in the cluster with the following command:
[student@nodename] $ | sudo -i
正解：
Create an nginx pod and list the pod with different levels of verbosity See the solution below.
正解：
// create a pod
kubectl run nginx --image=nginx --restart=Never --port=80
// List the pod with different verbosity
kubectl get po nginx --v=7
kubectl get po nginx --v=8
kubectl get po nginx --v=9
kubectl run nginx --image=nginx --restart=Never --port=80
// List the pod with different verbosity
kubectl get po nginx --v=7
kubectl get po nginx --v=8
kubectl get po nginx --v=9