Net Eng

[선수 작업]ssh node2 'sudo systemctl disable --now docker' >/dev/null 2>&1  [문제]A kubernetes worker node, named node2 is in state NotReady.Investigate why this is the case, and perform any appropriate steps bring the node to a Ready state, ensuring that any changes are made permanent.[풀이]kubectl get nodes* node 확인 ssh node2sudo -i* node2으로 접속 systemctl status docker* docker 상태 확인 systemctl enable --..

[선수 지식]Worker Node 동작원리 * Container Engine(Container Runtime) * kubelet * kube-proxy Worker Node Notready 상태라면, (ㄱ) dockerd running? (ㄴ) kubelet running? (ㄷ) kube-proxy running? (ㄹ) CNI running? Log Check * /var/log/{pods,containers}/ * container runtime command - docker: docker {ps,logs} - cri-o: crictl {ps,logs}   - containerd: nertdctl {ps,logs}  * kubelet logs: /var/log/syslog, journalctl   ..

[선수 지식]Kubernetes Cluster Upgrade  * Master Node(Controlplane) -> Upgrade(v1. * Worker Node -> Upgrade Kubernetes Cluster Component * Controlplane(apiserver, etcd, scheduler, controller, ..) * Worker node(kubelet, kube-proxy, container runtime, ..)   [선수 작업]kubectl config set-context k8s-master --user=kubernetes-admin --cluster=kubernetes  [문제]작업 클러스터: k8s-masterGiven an existing Kubernetes clus..

[선수 작업]kubectl config set-context k8s --user=kubernetes-admin --cluster=cluster.localkubectl apply -f -   [문제]작업 클러스터: k8sApplication Service 운영ingress-nginx namespace에 nginx 이미지를 app=nginx 레이블을 가지고 실행하는 nginx pod를 구성하시오.앞서 생성한 nginx pod를 서비스하는 nginx service를 생성하시오.현재 appjs-service Service는 이미 동작 중이다. 별도 구성이 필요 없다.Ingress 구성app-ingress.yaml 파일을 생성하여 다음 조건의 ingress 서비스를 구성하시오.ingress name: app-in..

[선수 작업]kubectl config set-context k8s --user=kubernetes-admin --cluster=kubernetesmkdir -p /var/CKA2023/mkdir -p /srv/app-config /srv/pv{1,2}kubectl apply -f -   [문제]작업 클러스터: k8sList all PV's sorted by name saving the full kubectl output to /var/CKA2023/my_volumes.Use kubectl’s own functionally for sorting the output, and do not manipulate it any further. [풀이]kubectl config use-context k8s* k8s ..

[선수 작업]kubectl config set-context k8s --user=kubernetes-admin --cluster=kubernetesmkdir -p /srv/pv{1,2}echo "/srv/pv1/index.html" > /srv/pv1/index.htmlecho "/src/pv2/index.html" > /srv/pv2/index.htmlkubectl apply -f -   [문제]작업 클러스터: k8sCreate a new PersistentVolumeClaim:Name: app-volumeStorageClass: app-hostpath-scCapacity: 10MiCreate a new Pod which mounts the PersistentVolumeClaim as a volume...

[선수 지식]1. 볼륨 종류 * hostPath * emptyDir * nfs + * iscsi, fc, ... 2. PV & PVC * PV   - 볼륨 정의(특성) * PVC  - 볼륨 요청(특성)  [선수 작업]kubectl config set-context k8s --user=kubernetes-admin --cluster=kubernetes  [문제]작업 클러스터: k8sCreate a persistent volume with name app-config, of capacity 1Gi and access mode ReadWriteMany.storageClass: az-cThe type of volume is hostPath and its location is /srv/app-config. [풀이..

[선수 작업]kubectl config set-context k8s --user=kubernetes-admin --cluster=kubernetes  [문제]작업 클러스터: k8sCreate a Kubernetes secret and expose using a file in the pod.Create a Kubernetes Secret as follows:Name: super-secretDATA: password=secretpassCreate a Pod named pod-secrets-via-file, using the redis image, which mounts a secret named super-secret at /secrets.Create a second Pod named pod-secrets-..