[KodeKloud | CKA ]LIGHTNING LABS, LIGHTNING LAB – 1

# LIGHTNING LABS, LIGHTNING LAB – 1 Q. 1 - *info_outline*Question Upgrade the current version of kubernetes from `1.25.0` to `1.26.0` exactly using the `kubeadm` utility. Make sure that the upgrade is carried out one node at a time starting with the controlplane node. To minimize downtime, the deployment `gold-nginx` should be rescheduled on an alternate node before upgrading each node. Upgrade `controlplane` node first and drain node `node01` before upgrading it. Pods for `gold-nginx` should run on the `controlplane` node subsequently. 현재 버전이 `1.25.0`인 쿠버네티스를 `kubeadm` 유틸리티를 사용하여 정확하게 `1.26.0`으로 업그레이드하십시오. 업그레이드는 컨트롤플레인 노드부터 한 번에 한 노드씩 수행되도록하십시오. 다운 타임을 최소화하기 위해 각 노드를 업그레이드하기 전에 `gold-nginx` 배포를 다른 노드로 재스케줄해야합니다. 먼저 `controlplane` 노드를 업그레이드하고 업그레이드하기 전에 `node01` 노드를 비워두십시오. `gold-nginx`의 Pods는 이후에 `controlplane` 노드에서 실행되어야합니다. - *info_outline*Solution Here is the solution for this task. Please note that the output of these commands have not been added here. On the `controlplane` node: ``` root@controlplane:~# kubectl drain controlplane --ignore-daemonsets root@controlplane:~# apt update root@controlplane:~# apt-get install kubeadm=1.26.0-00 root@controlplane:~# kubeadm upgrade plan v1.26.0 root@controlplane:~# kubeadm upgrade apply v1.26.0 root@controlplane:~# apt-get install kubelet=1.26.0-00 root@controlplane:~# systemctl daemon-reload root@controlplane:~# systemctl restart kubelet root@controlplane:~# kubectl uncordon controlplane ``` Before draining `node01`, we need to remove the taint from the `controlplane` node. `node01`을 비우기 전에 `controlplane` 노드에서 오염을 제거해야합니다. ``` # Identify the taint first. root@controlplane:~# kubectl describe node controlplane | grep -i taint # Remove the taint with help of "kubectl taint" command. root@controlplane:~# kubectl taint node controlplane node-role.kubernetes.io/control-plane:NoSchedule- # Verify it, the taint has been removed successfully. root@controlplane:~# kubectl describe node controlplane | grep -i taint ``` Now, drain the `node01` as follows: - ``` root@controlplane:~# kubectl drain node01 --ignore-daemonsets ``` `SSH` to the `node01` and perform the below steps as follows: ``` root@node01:~# apt update root@node01:~# apt-get install kubeadm=1.26.0-00 root@node01:~# kubeadm upgrade node root@node01:~# apt-get install kubelet=1.26.0-00 root@node01:~# systemctl daemon-reload root@node01:~# systemctl restart kubelet ``` To exit from the specific node, type `exit` or `logout` on the terminal. Back on the `controlplane` node: ``` root@controlplane:~# kubectl uncordon node01 root@controlplane:~# kubectl get pods -o wide | grep gold (make sure this is scheduled on node) ``` **CheckCompleteIncomplete** - *format_list_bulleted*Details Q. 2 - *info_outline*Question Print the names of all deployments in the `admin2406` namespace in the following format: - *info_outline*질문 다음 형식으로 `admin2406` 네임스페이스에 있는 모든 배포 이름을 출력하십시오: `DEPLOYMENT CONTAINER_IMAGE READY_REPLICAS NAMESPACE` ` ` . The data should be sorted by the increasing order of the `deployment name`. Example: `DEPLOYMENT CONTAINER_IMAGE READY_REPLICAS NAMESPACE` `deploy0 nginx:alpine 1 admin2406` Write the result to the file `/opt/admin2406_data`. - *info_outline*Solution Run the below command to get the correct output: ``` kubectl -n admin2406 get deployment -o custom-columns=DEPLOYMENT:.metadata.name,CONTAINER_IMAGE:.spec.template.spec.containers[].image,READY_REPLICAS:.status.readyReplicas,NAMESPACE:.metadata.namespace --sort-by=.metadata.name > /opt/admin2406_data ``` **CheckCompleteIncomplete** - *format_list_bulleted*Details Q. 3 - *info_outline*Question A kubeconfig file called `admin.kubeconfig` has been created in `/root/CKA`. There is something wrong with the configuration. Troubleshoot and fix it. - *info_outline*Solution Make sure the port for the `kube-apiserver` is correct. So for this change port from `4380` to `6443`. Run the below command to know the cluster information: ``` kubectl cluster-info --kubeconfig /root/CKA/admin.kubeconfig ``` **CheckCompleteIncomplete** - *format_list_bulleted*Details Q. 4 - *info_outline*Question Create a new deployment called `nginx-deploy`, with image `nginx:1.16` and `1` replica. Next upgrade the deployment to version `1.17` using `rolling update`. - *info_outline*Solution Make use of the `kubectl create` command to create the deployment and explore the `--record` option while upgrading the deployment image. Run the below command to create a deployment `nginx-deploy`: ``` kubectl create deployment nginx-deploy --image=nginx:1.16 ``` Run the below command to update the new image for `nginx-deploy` deployment and to record the version: ``` kubectl set image deployment/nginx-deploy nginx=nginx:1.17 --record ``` **CheckCompleteIncomplete** - *format_list_bulleted*Details Q. 5 - *info_outline*Question A new deployment called `alpha-mysql` has been deployed in the `alpha` namespace. However, the pods are not running. Troubleshoot and fix the issue. The deployment should make use of the persistent volume `alpha-pv` to be mounted at `/var/lib/mysql` and should use the environment variable `MYSQL_ALLOW_EMPTY_PASSWORD=1` to make use of an empty root password. 새로운 배포인 `alpha-mysql`이 `alpha` 네임스페이스에 배포되었습니다. 그러나 파드가 실행되지 않습니다. 문제를 해결하십시오. 배포는 영구 볼륨 `alpha-pv`를 사용하여 `/var/lib/mysql`에 마운트해야하며 빈 루트 암호를 사용하기 위해 환경 변수 `MYSQL_ALLOW_EMPTY_PASSWORD=1`을 사용해야합니다. Important: Do not alter the persistent volume. - *info_outline*Solution Use the command `kubectl describe` and try to fix the issue. Solution manifest file to create a pvc called `mysql-alpha-pvc` as follows: ``` --- apiVersion: v1 kind: PersistentVolumeClaim metadata: name: mysql-alpha-pvc namespace: alpha spec: accessModes: - ReadWriteOnce resources: requests: storage: 1Gi storageClassName: slow ``` **CheckCompleteIncomplete** - *format_list_bulleted*Details Q. 6 - *info_outline*Question Take the backup of ETCD at the location `/opt/etcd-backup.db` on the `controlplane` node. - *info_outline*Solution **CheckCompleteIncomplete** - *format_list_bulleted*Details Q. 7 - *info_outline*Question Create a pod called `secret-1401` in the `admin1401` namespace using the `busybox` image. The container within the pod should be called `secret-admin` and should sleep for `4800` seconds. The container should mount a `read-only` secret volume called `secret-volume` at the path `/etc/secret-volume`. The secret being mounted has already been created for you and is called `dotfile-secret`. - *info_outline*질문 `admin1401` 네임스페이스에 `busybox` 이미지를 사용하여 `secret-1401`이라는 파드를 만듭니다. 파드 내부의 컨테이너는 `secret-admin`이라는 이름이어야하며 `4800`초 동안 슬립해야합니다. 컨테이너는 `/etc/secret-volume` 경로에서 `read-only` 비밀 볼륨 `secret-volume`을 마운트해야합니다. 마운트되는 비밀은 이미 `dotfile-secret`라는 이름으로 생성되었습니다. Use the command `kubectl run` to create a pod definition file. Add secret volume and update container name in it. Alternatively, run the following command: ``` kubectl run secret-1401 -n admin1401 --image=busybox --dry-run=client -oyaml --command -- sleep 4800 > admin.yaml ``` Add the `secret` volume and mount path to create a pod called `secret-1401` in the `admin1401` namespace as follows: ``` --- apiVersion: v1 kind: Pod metadata: creationTimestamp:nulllabels: run: secret-1401 name: secret-1401 namespace: admin1401 spec: volumes: - name: secret-volume # secret volume secret: secretName: dotfile-secret containers: - command: - sleep - "4800" image: busybox name: secret-admin # volumes' mount path volumeMounts: - name: secret-volume readOnly:truemountPath: "/etc/secret-volume" ```