쿠버네티스 주요명령어 모음

# 해당 pod가 어느 node에 있는지 확인하기

kubectl get pod -o wide

ec2-user:~/environment/yaml $ kubectl get pod -o wide
NAME                              READY   STATUS    RESTARTS   AGE   IP       NODE     NOMINATED NODE   READINESS GATES
deploy-jenkins-7dcdf75b94-7zrjx   0/1     Pending   0          54m   <none>   <none>   <none>           <none>
deploy-jenkins-7dcdf75b94-gngq8   0/1     Pending   0          62m   <none>   <none>   <none>           <none>
deploy-jenkins-7dcdf75b94-hbr5l   0/1     Pending   0          58m   <none>   <none>   <none>           <none>
deploy-jenkins-7dcdf75b94-r2tq4   0/1     Pending   0          62m   <none>   <none>   <none>           <none>
deploy-jenkins-7dcdf75b94-t2j8f   0/1     Pending   0          61m   <none>   <none>   <none>           <none>
ec2-user:~/environment/yaml $

- 하나의 pod가 어느 노드에 있는지 확인하기

kubectl get pod deploy-jenkins-7dcdf75b94-7zrjx -o wide
kubectl get pod [#podname] -o wide

ec2-user:~/environment/yaml $ kubectl get pod deploy-jenkins-7dcdf75b94-7zrjx -o wide
NAME                              READY   STATUS    RESTARTS   AGE   IP       NODE     NOMINATED NODE   READINESS GATES
deploy-jenkins-7dcdf75b94-7zrjx   0/1     Pending   0          59m   <none>   <none>   <none>           <none>
ec2-user:~/environment/yaml $

# edit 명령어를 사용하여 스케일 아웃 수행하기

#rs 조회
kubectl get rs
#rs 수정
kubectl edit rs rs-nginx
kubectl edit rs [#replicaset name]

- replicas 수를 변경하면 스케일 아웃과 스케일 인을 설정 할 수 있다.

spec:
  replicas: 3
  selector:
    matchLabels:
      app: rs-nginx
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: rs-nginx

# 모든 namespace에 있는 pod 조회하기

kubectl get pod --all-namespaces

# 특정 이름으로 정의된 namespace pod를 조회하기

kubectl get pods --namespace prometheus
kubectl get pods --namespace [#정의된namespace]

ec2-user:~/environment/grafana_prometheus $ kubectl get pods --namespace prometheus 
NAME                                             READY   STATUS    RESTARTS   AGE
grafana-5d76d7b7b9-vq5w6                         0/1     Pending   0          14m
prometheus-alertmanager-5d577c9bf4-bzfxr         0/2     Pending   0          26m
prometheus-kube-state-metrics-569d7854c4-2gcdh   0/1     Pending   0          15m
prometheus-node-exporter-4pdcn                   0/1     Pending   0          15m
prometheus-node-exporter-jl8k6                   0/1     Pending   0          26m
prometheus-node-exporter-tsvvp                   0/1     Pending   0          13m
prometheus-pushgateway-6c5fd69fd6-wbl56          0/1     Pending   0          26m
prometheus-server-6c6f6669b6-m97cq               0/2     Pending   0          26m
ec2-user:~/environment/grafana_prometheus $

- 간혹 kebectl get pod로 조회가 되지 않는 경우가 있다. 아래처럼 말이다.
이럴때는 위에서 설명한 것과 같이 namespace를 따로 정의해서 조회를 해주면 된다.

ec2-user:~/environment/grafana_prometheus $ kubectl get pods
No resources found in default namespace.

# 기본 네임스페이스외 모든 네임스페이스 삭제하기

kubectl delete namespace --all

- 기본 디폴트 namespace만 제외하고 모든 namespace가 삭제된다.

ec2-user:~/environment $ kubectl delete namespace --all
namespace "kube-node-lease" deleted
namespace "prometheus" deleted
Error from server (Forbidden): namespaces "default" is forbidden: this namespace may not be deleted
Error from server (Forbidden): namespaces "kube-public" is forbidden: this namespace may not be deleted
Error from server (Forbidden): namespaces "kube-system" is forbidden: this namespace may not be deleted
ec2-user:~/environment $

# 특정 네임스페이스와 svc를 조회하기

ec2-user:~/environment/efk $ kubectl get pod,svc -n prometheus 
NAME                                                 READY   STATUS              RESTARTS   AGE
pod/grafana-76585bffbf-7q6pl                         0/1     Init:0/1            0          45m
pod/prometheus-alertmanager-787f86875f-sbjsk         0/2     Pending             0          7h29m
pod/prometheus-kube-state-metrics-58c5cd6ddb-kcrb7   1/1     Running             0          45m
pod/prometheus-node-exporter-gtmnb                   1/1     Running             0          42m
pod/prometheus-pushgateway-6bd6fcd9b8-68vzj          1/1     Running             0          45m
pod/prometheus-server-75897d656d-zk5gp               0/2     ContainerCreating   0          45m

NAME                                    TYPE           CLUSTER-IP       EXTERNAL-IP                                                                   PORT(S)        AGE
service/grafana                         LoadBalancer   10.100.235.83    a8233b01bf6b94e07bfe4847fe4f6349-198417945.ap-northeast-2.elb.amazonaws.com   80:30704/TCP   8h
service/prometheus-alertmanager         ClusterIP      10.100.150.140   <none>                                                                        80/TCP         8h
service/prometheus-kube-state-metrics   ClusterIP      10.100.189.191   <none>                                                                        8080/TCP       8h
service/prometheus-node-exporter        ClusterIP      None             <none>                                                                        9100/TCP       8h
service/prometheus-pushgateway          ClusterIP      10.100.234.8     <none>                                                                        9091/TCP       8h
service/prometheus-server               ClusterIP      10.100.90.151    <none>

# 로그 확인

kubectl logs [NAME]

kubectl logs jenkins-7ffb988b7-jwnjw

# ALB 자격증명 확인

kubectl describe ingress nginx-ingress
kubectl describe deploy <aws-load-balancer-controller> -n kube-system | grep -i "Service Account"
kubectl get deployment -n kube-system aws-load-balancer-controller
kubectl describe deploy aws-load-balancer-controller -n kube-system | grep -i "Service Account"
kubectl describe sa aws-load-balancer-controller -n kube-system
kubectl describe ingress nginx-ingress