Udemy Labs - Certified Kubernetes Application Developer - Lab: Lightning Lab - 2 문제 풀이

hyereen·2025년 1월 30일

Kubernetes

목록 보기

34/53

1/5
We have deployed a few pods in this cluster in various namespaces. Inspect them and identify the pod which is not in a Ready state. Troubleshoot and fix the issue.
Next, add a check to restart the container on the same pod if the command ls /var/www/html/file_check fails. This check should start after a delay of 10 seconds and run every 60 seconds.
You may delete and recreate the object. Ignore the warnings from the probe.

참고

Define a TCP liveness probe: https://kubernetes.io/docs/tasks/configure-pod-container/configure-liveness-readiness-startup-probes/#define-a-tcp-liveness-probe

정답
1. 에러 파드 확인

controlplane ~ ➜  kubectl get pods --all-namespaces
NAMESPACE     NAME                                       READY   STATUS    RESTARTS   AGE
default       dev-pod-dind-878516                        3/3     Running   0          39s
default       pod-xyz1123                                1/1     Running   0          39s
default       webapp-color                               1/1     Running   0          38s
dev0403       nginx0403                                  1/1     Running   0          39s
dev0403       pod-dar85                                  1/1     Running   0          39s
dev1401       nginx1401                                  0/1     Running   0          39s

controlplane ~ ➜  k describe po nginx1401 -n dev1401
Name:             nginx1401
Namespace:        dev1401
Priority:         0
Service Account:  default
Node:             node01/192.168.139.50
Start Time:       Thu, 30 Jan 2025 10:31:54 +0000
Labels:           run=nginx
Annotations:      cni.projectcalico.org/containerID: 9d62220f765425a9ea5b4003d6f827493b8e64d35cc155c86a3128a773578c90
                  cni.projectcalico.org/podIP: 172.17.1.2/32
                  cni.projectcalico.org/podIPs: 172.17.1.2/32
Status:           Running
IP:               172.17.1.2
IPs:
  IP:  172.17.1.2
Containers:
  nginx:
    Container ID:   containerd://ad1b44c2d69fa98694620d673693f930eff723c0e658ef9b4aacba93767e3579
    Image:          kodekloud/nginx
    Image ID:       docker.io/kodekloud/nginx@sha256:2862900861517dfaf9e0ed0f4fa199744a7410f4f78520866031c725c386bb5e
    Port:           9080/TCP
    Host Port:      0/TCP
    State:          Running
      Started:      Thu, 30 Jan 2025 10:32:00 +0000
    Ready:          False
    Restart Count:  0
    Readiness:      http-get http://:8080/ delay=0s timeout=1s period=10s #success=1 #failure=3
    Environment:    <none>
    Mounts:
      /var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-tggbm (ro)
Conditions:
  Type                        Status
  PodReadyToStartContainers   True 
  Initialized                 True 
  Ready                       False 
  ContainersReady             False 
  PodScheduled                True 
Volumes:
  kube-api-access-tggbm:
    Type:                    Projected (a volume that contains injected data from multiple sources)
    TokenExpirationSeconds:  3607
    ConfigMapName:           kube-root-ca.crt
    ConfigMapOptional:       <nil>
    DownwardAPI:             true
QoS Class:                   BestEffort
Node-Selectors:              <none>
Tolerations:                 node.kubernetes.io/not-ready:NoExecute op=Exists for 300s
                             node.kubernetes.io/unreachable:NoExecute op=Exists for 300s
Events:
  Type     Reason     Age                 From               Message
  ----     ------     ----                ----               -------
  Normal   Scheduled  10m                 default-scheduler  Successfully assigned dev1401/nginx1401 to node01
  Normal   Pulling    10m                 kubelet            Pulling image "kodekloud/nginx"
  Normal   Pulled     10m                 kubelet            Successfully pulled image "kodekloud/nginx" in 4.429s (4.429s including waiting). Image size: 50986074 bytes.
  Normal   Created    10m                 kubelet            Created container nginx
  Normal   Started    10m                 kubelet            Started container nginx
  Warning  Unhealthy  28s (x70 over 10m)  kubelet            Readiness probe failed: Get "http://172.17.1.2:8080/": dial tcp 172.17.1.2:8080: connect: connection refused

controlplane ~ ➜

yaml파일 수정

apiVersion: v1
kind: Pod
metadata:
  labels:
    run: nginx
  name: nginx1401
  namespace: dev1401
spec:
  containers:
  - image: kodekloud/nginx
    imagePullPolicy: IfNotPresent
    name: nginx
    ports:
    - containerPort: 9080
      protocol: TCP
    readinessProbe:
      httpGet:
        path: /
        port: 9080    
    livenessProbe:
      exec:
        command:
        - ls
        - /var/www/html/file_check
      initialDelaySeconds: 10
      periodSeconds: 60

2 / 5
Weight: 20
Create a cronjob called dice that runs every one minute. Use the Pod template located at /root/throw-a-dice. The image throw-dice randomly returns a value between 1 and 6. The result of 6 is considered success and all others are failure.
The job should be non-parallel and complete the task once. Use a backoffLimit of 25.
If the task is not completed within 20 seconds the job should fail and pods should be terminated.
You don't have to wait for the job completion. As long as the cronjob has been created as per the requirements.

참고:

정답

controlplane ~ ➜  cat dice.yaml 
apiVersion: batch/v1
kind: CronJob
metadata:
  name: dice
spec:
  schedule: "1 * * * *"
  jobTemplate:
    spec:
      backoffLimit: 25
      activeDeadlineSeconds: 20
      template:
        spec:
          containers:
          - image: kodekloud/throw-dice
            name: throw-dice
          restartPolicy: Never

3 / 5
Weight: 20
Create a pod called my-busybox in the dev2406 namespace using the busybox image. The container should be called secret and should sleep for 3600 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.
Make sure that the pod is scheduled on controlplane and no other node in the cluster.
Pod created correctly?

참고

secret volume: https://kubernetes.io/docs/concepts/configuration/secret/#use-case-dotfiles-in-a-secret-volume
pod scheduled to specific node: https://kubernetes.io/docs/tasks/configure-pod-container/assign-pods-nodes/#create-a-pod-that-gets-scheduled-to-specific-node

정답

controlplane ~ ➜  cat my-busybox.yaml 
apiVersion: v1
kind: Pod
metadata:
  name: my-busybox
  namespace: dev2406
spec:
  nodeSelector:
    kubernetes.io/hostname: controlplane
  volumes:
    - name: secret-volume
      secret:
        secretName: dotfile-secret
  containers:
  - name: secret
    image: busybox
    command:
      - sleep
    args:
      - "3600"
    volumeMounts:
      - name: secret-volume
        readOnly: true
        mountPath: "/etc/secret-volume"

또는

controlplane ~ ➜  cat my-busybox.yaml 
apiVersion: v1
kind: Pod
metadata:
  name: my-busybox
  namespace: dev2406
spec:
  nodeName: controlplane
  volumes:
    - name: secret-volume
      secret:
        secretName: dotfile-secret
  containers:
  - name: secret
    image: busybox
    command:
      - sleep
    args:
      - "3600"
    volumeMounts:
      - name: secret-volume
        readOnly: true
        mountPath: "/etc/secret-volume"

4 / 5
Weight: 20
Create a single ingress resource called ingress-vh-routing. The resource should route HTTP traffic to multiple hostnames as specified below:
The service video-service should be accessible on http://watch.ecom-store.com:30093/video
The service apparels-service should be accessible on http://apparels.ecom-store.com:30093/wear
To ensure that the path is correctly rewritten for the backend service, add the following annotation to the resource:
nginx.ingress.kubernetes.io/rewrite-target: /
Here 30093 is the port used by the Ingress Controller
Ingress resource configured correctly?

참고

ingress annotation: https://kubernetes.io/docs/concepts/services-networking/ingress/#the-ingress-resource
ingress host: https://kubernetes.io/docs/concepts/services-networking/ingress/#hostname-wildcards

정답

그리고 솔루션 답을 똑같이 복붙해서 k apply -f 해도 자꾸 틀렸다고 뜬다;; 왜이럴까 -> 4번 문제를 가서 svc가 셋팅된걸 보고 문제를 풀어야함..
svc의 port가 8080이니까 ingress의 port도 8080으로 맞춰줘야 함

controlplane ~ ➜  k get svc
NAME               TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)    AGE
apparels-service   ClusterIP   172.20.77.7      <none>        8080/TCP   4s
kubernetes         ClusterIP   172.20.0.1       <none>        443/TCP    8m2s
video-service      ClusterIP   172.20.201.219   <none>        8080/TCP   4s

kind: Ingress
apiVersion: networking.k8s.io/v1
metadata:
  name: ingress-vh-routing
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: / # 빼먹지말기
spec:
  rules:
  - host: watch.ecom-store.com # 쌍따옴표 없음
    http:
      paths:
      - pathType: Prefix
        path: "/video" # 쌍따옴표있음
        backend:
          service:
            name: video-service
            port:
              number: 8080
  - host: apparels.ecom-store.com
    http:
      paths:
      - pathType: Prefix
        path: "/wear"
        backend:
          service:
            name: apparels-service
            port:
              number: 8080

5 / 5
Weight: 20
A pod called dev-pod-dind-878516 has been deployed in the default namespace. Inspect the logs for the container called log-x and redirect the warnings to /opt/dind-878516_logs.txt on the controlplane node
Redirect warnings to file

정답

-c: 파드 내에 여러 컨테이너가 있을 경우, -c 옵션을 통해 특정 컨테이너를 지정할 수 있음

controlplane ~ ➜  k logs dev-pod-dind-878516 -c log-x | grep WARNING > /opt/dind-878516_logs.txt

controlplane ~ ✖ cat /opt/dind-878516_logs.txt
[2025-01-30 12:10:12,562] WARNING in event-simulator: USER5 Failed to Login as the account is locked due to MANY FAILED ATTEMPTS.
[2025-01-30 12:10:15,564] WARNING in event-simulator: USER7 Order failed as the item is OUT OF STOCK.
[2025-01-30 12:10:17,567] WARNING in event-simula

hyereen

이전 포스트

Udemy Labs - Certified Kubernetes Application Developer - Lab: Lightning Lab - 1 문제 풀이

다음 포스트

Udemy Labs - Certified Kubernetes Application Developer - Lab: Lightning Lab - 2 문제 풀이

Kubernetes

Udemy Labs - Certified Kubernetes Application Developer - Lab: Lightning Lab - 1 문제 풀이

Udemy Labs - Certified Kubernetes Application Developer - Mock Exam - 1 문제 풀이

0개의 댓글