7. 오라클 클라우드 - 쿠버네티스 - 리플리카세트

by Master Seo

Feb 21. 2023

<1> 컨트롤러?

<2> ReplicaSet ?

<3> 리플리카셋 실습

<4> 죽지 않는 pod - 리플리카셋이 관리하고 있음

<5> 디플로이 먼트 실습

<6> 롤링 업데이트와 롤백

<1> 컨트롤러?

모니터링하며, 원하는 상태가 되도록 만들어 주는것이 컨트롤러 이다.

<2> ReplicaSet ?

Pod의 수를 일정 갯수로 유지 되도록 해주는것

아래 예제에서 3개의 Pod를 유지해보자~

topasvga@cloudshell:~ (ap-seoul-1)$ cat << EOF > replicaset-cndk.yaml

> apiVersion: apps/v1

> kind: ReplicaSet

> metadata:

> name: replicaset-cndk

> spec:

> replicas: 3

> selector:

> matchLabels:

> app: cndk-nginx-pods

> template:

> metadata:

> name: cndk-nginx-pod

> labels:

> app: cndk-nginx-pods

> spec:

> containers:

> - name: nginx

> image: nginx:latest

> EOF

10 replicaset-cndk.yaml

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl apply -f replicaset-cndk.yaml

replicaset.apps/replicaset-cndk created

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pods,rs,deploy -o wide

NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES

pod/replicaset-cndk-24zqg 1/1 Running 0 24s 10.244.0.30 10.0.10.80 <none> <none>

pod/replicaset-cndk-hn8x5 1/1 Running 0 24s 10.244.0.31 10.0.10.80 <none> <none>

pod/replicaset-cndk-s47mh 1/1 Running 0 24s 10.244.0.141 10.0.10.141 <none> <none>

NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR

replicaset.apps/replicaset-cndk 3 3 3 24s nginx nginx:latest app=cndk-nginx-pods

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl describe replicasets.apps replicaset-cndk

Name: replicaset-cndk

Namespace: default

Selector: app=cndk-nginx-pods

Labels: <none>

Annotations: <none>

Replicas: 3 current / 3 desired

Pods Status: 3 Running / 0 Waiting / 0 Succeeded / 0 Failed

Pod Template:

Labels: app=cndk-nginx-pods

Containers:

nginx:

Image: nginx:latest

Port: <none>

Host Port: <none>

Environment: <none>

Mounts: <none>

Volumes: <none>

Events:

Type Reason Age From Message

---- ------ ---- ---- -------

Normal SuccessfulCreate 84s replicaset-controller Created pod: replicaset-cndk-hn8x5

Normal SuccessfulCreate 84s replicaset-controller Created pod: replicaset-cndk-s47mh

Normal SuccessfulCreate 84s replicaset-controller Created pod: replicaset-cndk-24zqg

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pod --show-labels

NAME READY STATUS RESTARTS AGE LABELS

replicaset-cndk-24zqg 1/1 Running 0 111s app=cndk-nginx-pods

replicaset-cndk-hn8x5 1/1 Running 0 111s app=cndk-nginx-pods

replicaset-cndk-s47mh 1/1 Running 0 111s app=cndk-nginx-pods

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl edit replicasets.apps replicaset-cndk

replicaset.apps/replicaset-cndk edited

spec:

replicas: 6

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pods

NAME READY STATUS RESTARTS AGE

replicaset-cndk-24zqg 1/1 Running 0 2m42s

replicaset-cndk-hn8x5 1/1 Running 0 2m42s

replicaset-cndk-qlv2k 1/1 Running 0 14s

replicaset-cndk-s47mh 1/1 Running 0 2m42s

replicaset-cndk-wg6bm 1/1 Running 0 14s

replicaset-cndk-xjw77 1/1 Running 0 14s

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl delete replicasets.apps replicaset-cndk

replicaset.apps "replicaset-cndk" deleted

<3> 리플리카셋 실습

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl apply -f replicaset-cndk.yaml

replicaset.apps/replicaset-cndk created

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get rs,deploy

NAME DESIRED CURRENT READY AGE

replicaset.apps/replicaset-cndk 3 3 3 17s

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get replicasets.apps -o wide

NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR

replicaset-cndk 3 3 3 93s nginx nginx:latest app=cndk-nginx-pods

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pods

NAME READY STATUS RESTARTS AGE

replicaset-cndk-9tflm 1/1 Running 0 2m18s

replicaset-cndk-c2bk4 1/1 Running 0 2m18s

replicaset-cndk-pw85g 1/1 Running 0 2m18s

중복되는 Label의 Pod 생성하면 ?

생성되자 마자 죽는다!!

topasvga@cloudshell:~ (ap-seoul-1)$ cat << EOF > pod-rs.yaml

> apiVersion: v1

> kind: Pod

> metadata:

> name: pod1

> labels:

> app: cndk-nginx-pods

> spec:

> containers:

> - name: hello1

> image: gcr.io/google-samples/hello-app:1.0

> ---

> apiVersion: v1

> kind: Pod

> metadata:

> name: pod2

> labels:

> app: cndk-nginx-pods

> spec:

> containers:

> - name: hello2

> image: gcr.io/google-samples/hello-app:2.0

> EOF

30 rs (1).txt

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl apply -f pod-rs.yaml && kubectl get pod -w

pod/pod1 created

pod/pod2 created

NAME READY STATUS RESTARTS AGE

pod1 0/1 Terminating 0 2s

pod2 0/1 Terminating 0 2s

replicaset-cndk-9tflm 1/1 Running 0 2m59s

replicaset-cndk-c2bk4 1/1 Running 0 2m59s

replicaset-cndk-pw85g 1/1 Running 0 2m59s

pod1 1/1 Terminating 0 5s

pod2 1/1 Terminating 0 5s

pod1 0/1 Terminating 0 6s

pod2 0/1 Terminating 0 6s

<4> 죽지 않는 pod - 리플리카셋이 관리하고 있음

topasvga@cloudshell:~ (ap-seoul-1)kubectl get pods

NAME READY STATUS RESTARTS AGE

replicaset-cndk-9tflm 1/1 Running 0 3m41s

replicaset-cndk-c2bk4 1/1 Running 0 3m41s

replicaset-cndk-pw85g 1/1 Running 0 3m41s

pod 삭제한다.

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl delete pod -l app=cndk-nginx-pods

pod "replicaset-cndk-9tflm" deleted

pod "replicaset-cndk-c2bk4" deleted

pod "replicaset-cndk-pw85g" deleted

새로 3개 자동 생성 된다.

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pod -w

NAME READY STATUS RESTARTS AGE

replicaset-cndk-9w8cj 1/1 Running 0 7s

replicaset-cndk-pghzz 1/1 Running 0 7s

replicaset-cndk-tvjf8 1/1 Running 0 6s

라벨 확인

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pod --show-labels

NAME READY STATUS RESTARTS AGE LABELS

replicaset-cndk-9w8cj 1/1 Running 0 37s app=cndk-nginx-pods

replicaset-cndk-pghzz 1/1 Running 0 37s app=cndk-nginx-pods

replicaset-cndk-tvjf8 1/1 Running 0 36s app=cndk-nginx-pods

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl label pod replicaset-cndk-9w8cj app-

pod/replicaset-cndk-9w8cj unlabeled

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pod --show-labels

NAME READY STATUS RESTARTS AGE LABELS

replicaset-cndk-62x24 1/1 Running 0 8s app=cndk-nginx-pods

replicaset-cndk-9w8cj 1/1 Running 0 116s <none>

replicaset-cndk-pghzz 1/1 Running 0 116s app=cndk-nginx-pods

replicaset-cndk-tvjf8 1/1 Running 0 115s app=cndk-nginx-pods

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl delete rs replicaset-cndk

replicaset.apps "replicaset-cndk" deleted

라벨 지워져 없는것은 안지워 진다.

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pod --show-labels

NAME READY STATUS RESTARTS AGE LABELS

replicaset-cndk-9w8cj 1/1 Running 0 2m28s <none>

파드 삭제하기

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl delete pod --all

pod "replicaset-cndk-9w8cj" deleted

<5> 디플로이 먼트 실습

topasvga@cloudshell:~ (ap-seoul-1)$ cat << EOF > deployment-cndk.yaml

> apiVersion: apps/v1

> kind: Deployment

> metadata:

> name: deployment-cndk

> spec:

> replicas: 3

> selector:

> matchLabels:

> app: cndk-nginx-pods

> template:

> metadata:

> name: cndk-nginx-pod

> labels:

> app: cndk-nginx-pods

> spec:

> containers:

> - name: nginx

> image: nginx:latest

> EOF

40 deploy (1).txt

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl apply -f deployment-cndk.yaml

deployment.apps/deployment-cndk created

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get deploy,rs,pods

NAME READY UP-TO-DATE AVAILABLE AGE

deployment.apps/deployment-cndk 3/3 3 3 12s

NAME DESIRED CURRENT READY AGE

replicaset.apps/deployment-cndk-76bc4fd57f 3 3 3 12s

NAME READY STATUS RESTARTS AGE

pod/deployment-cndk-76bc4fd57f-h5m4c 1/1 Running 0 13s

pod/deployment-cndk-76bc4fd57f-st7c6 1/1 Running 0 13s

pod/deployment-cndk-76bc4fd57f-tlhbx 1/1 Running 0 13s

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get deployments.apps -o wide

NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR

deployment-cndk 3/3 3 3 2m26s nginx nginx:latest app=cndk-nginx-pods

topasvga@cloudshell:~ (ap-seoul-1)$

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get replicasets.apps -o wide

NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR

deployment-cndk-76bc4fd57f 3 3 3 2m42s nginx nginx:latest app=cndk-nginx-pods,pod-template-hash=76bc4fd57f

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pod --show-labels

NAME READY STATUS RESTARTS AGE LABELS

deployment-cndk-76bc4fd57f-h5m4c 1/1 Running 0 3m3s app=cndk-nginx-pods,pod-template-hash=76bc4fd57f

deployment-cndk-76bc4fd57f-st7c6 1/1 Running 0 3m3s app=cndk-nginx-pods,pod-template-hash=76bc4fd57f

deployment-cndk-76bc4fd57f-tlhbx 1/1 Running 0 3m3s app=cndk-nginx-pods,pod-template-hash=76bc4fd57f

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl scale deployment --replicas=6 deployment-cndk

deployment.apps/deployment-cndk scaled

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pod --show-labels

NAME READY STATUS RESTARTS AGE LABELS

deployment-cndk-76bc4fd57f-9n7fs 1/1 Running 0 38s app=cndk-nginx-pods,pod-template-hash=76bc4fd57f

deployment-cndk-76bc4fd57f-h5m4c 1/1 Running 0 3m55s app=cndk-nginx-pods,pod-template-hash=76bc4fd57f

deployment-cndk-76bc4fd57f-mw87z 1/1 Running 0 38s app=cndk-nginx-pods,pod-template-hash=76bc4fd57f

deployment-cndk-76bc4fd57f-st7c6 1/1 Running 0 3m55s app=cndk-nginx-pods,pod-template-hash=76bc4fd57f

deployment-cndk-76bc4fd57f-tgn88 1/1 Running 0 38s app=cndk-nginx-pods,pod-template-hash=76bc4fd57f

deployment-cndk-76bc4fd57f-tlhbx 1/1 Running 0 3m55s app=cndk-nginx-pods,pod-template-hash=76bc4fd57f

pod 삭제

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl delete pod --all

pod "deployment-cndk-76bc4fd57f-9n7fs" deleted

pod "deployment-cndk-76bc4fd57f-h5m4c" deleted

pod "deployment-cndk-76bc4fd57f-mw87z" deleted

pod "deployment-cndk-76bc4fd57f-st7c6" deleted

pod "deployment-cndk-76bc4fd57f-tgn88" deleted

pod "deployment-cndk-76bc4fd57f-tlhbx" deleted

다시 자동 생성된다

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pod

NAME READY STATUS RESTARTS AGE

deployment-cndk-76bc4fd57f-4tqtx 1/1 Running 0 19s

deployment-cndk-76bc4fd57f-8nmzb 1/1 Running 0 18s

deployment-cndk-76bc4fd57f-hrk5s 1/1 Running 0 19s

deployment-cndk-76bc4fd57f-mwt8q 1/1 Running 0 19s

deployment-cndk-76bc4fd57f-nnmsx 1/1 Running 0 19s

deployment-cndk-76bc4fd57f-w5ftv 1/1 Running 0 19s

리플리카 삭제

다시 살아 난다.

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl delete replicasets.apps --all

replicaset.apps "deployment-cndk-76bc4fd57f" deleted

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get deploy,rs,pod

NAME READY UP-TO-DATE AVAILABLE AGE

deployment.apps/deployment-cndk 6/6 6 6 5m20s

NAME DESIRED CURRENT READY AGE

replicaset.apps/deployment-cndk-76bc4fd57f 6 6 6 25s

NAME READY STATUS RESTARTS AGE

pod/deployment-cndk-76bc4fd57f-6c8xz 1/1 Running 0 24s

pod/deployment-cndk-76bc4fd57f-c7n6f 1/1 Running 0 25s

pod/deployment-cndk-76bc4fd57f-lv524 1/1 Running 0 24s

pod/deployment-cndk-76bc4fd57f-pz5md 1/1 Running 0 24s

pod/deployment-cndk-76bc4fd57f-vv4hn 1/1 Running 0 24s

pod/deployment-cndk-76bc4fd57f-zdz2d 1/1 Running 0 24s

디플로이먼트 삭제

디플로이먼트를 삭제하면 모두 삭제 된다.

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl delete deployments.apps deployment-cndk

deployment.apps "deployment-cndk" deleted

확인

모두 삭제 되었다.

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get deploy,rs,pod

No resources found in default namespace.

<6> 롤링 업데이트와 롤백

topasvga@cloudshell:~ (ap-seoul-1)$ cat << EOF > deployment-nginx-1.yaml

> apiVersion: apps/v1

> kind: Deployment

> metadata:

> name: deployment-nginx

> spec:

> replicas: 3

> selector:

> matchLabels:

> app: cndk-nginx-pods

> template:

> metadata:

> name: cndk-nginx-pod

> labels:

> app: cndk-nginx-pods

> spec:

> containers:

> - name: nginx

> image: nginx:1.11

> EOF

50 rolling.txt

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl apply -f deployment-nginx-1.yaml --record

Flag --record has been deprecated, --record will be removed in the future

deployment.apps/deployment-nginx created

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pod -o yaml | grep "image: nginx"

- image: nginx:1.11

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl rollout history deployment deployment-nginx

deployment.apps/deployment-nginx

REVISION CHANGE-CAUSE

1 kubectl apply --filename=deployment-nginx-1.yaml --record=true

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl set image deployment deployment-nginx nginx=nginx:1.12 --record && kubectl get pod -w

Flag --record has been deprecated, --record will be removed in the future

deployment.apps/deployment-nginx image updated

NAME READY STATUS RESTARTS AGE

deployment-nginx-558dfc6f84-4zrgr 0/1 ContainerCreating 0 2s

deployment-nginx-775869fd7-257pb 1/1 Running 0 46s

deployment-nginx-775869fd7-jc8wm 1/1 Running 0 46s

deployment-nginx-775869fd7-ndtz4 1/1 Running 0 46s

deployment-nginx-558dfc6f84-4zrgr 1/1 Running 0 10s

deployment-nginx-775869fd7-ndtz4 1/1 Terminating 0 54s

deployment-nginx-558dfc6f84-spqvn 0/1 Pending 0 0s

deployment-nginx-558dfc6f84-spqvn 0/1 ContainerCreating 0 0s

deployment-nginx-775869fd7-ndtz4 0/1 Terminating 0 56s

deployment-nginx-558dfc6f84-spqvn 1/1 Running 0 11s

deployment-nginx-775869fd7-jc8wm 1/1 Terminating 0 65s

deployment-nginx-558dfc6f84-sjxn8 0/1 Pending 0 0s

deployment-nginx-558dfc6f84-sjxn8 0/1 ContainerCreating 0 0s

deployment-nginx-558dfc6f84-sjxn8 1/1 Running 0 2s

deployment-nginx-775869fd7-257pb 1/1 Terminating 0 67s

deployment-nginx-775869fd7-jc8wm 0/1 Terminating 0 67s

deployment-nginx-775869fd7-257pb 0/1 Terminating 0 68s

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pod -o yaml | grep "image: nginx"

- image: nginx:1.12

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl set image deployment deployment-nginx nginx=nginx:1.13 --record && kubectl get pod -w

Flag --record has been deprecated, --record will be removed in the future

deployment.apps/deployment-nginx image updated

NAME READY STATUS RESTARTS AGE

deployment-nginx-558dfc6f84-4zrgr 1/1 Running 0 60s

deployment-nginx-558dfc6f84-sjxn8 1/1 Running 0 39s

deployment-nginx-558dfc6f84-spqvn 1/1 Running 0 50s

deployment-nginx-c9cc67877-hlns2 0/1 ContainerCreating 0 3s

deployment-nginx-c9cc67877-hlns2 1/1 Running 0 9s

deployment-nginx-558dfc6f84-spqvn 1/1 Terminating 0 56s

deployment-nginx-c9cc67877-ft6t7 0/1 Pending 0 0s

deployment-nginx-c9cc67877-ft6t7 0/1 ContainerCreating 0 0s

deployment-nginx-558dfc6f84-spqvn 0/1 Terminating 0 57s

deployment-nginx-c9cc67877-ft6t7 1/1 Running 0 10s

deployment-nginx-558dfc6f84-sjxn8 1/1 Terminating 0 55s

deployment-nginx-c9cc67877-r2whn 0/1 Pending 0 0s

deployment-nginx-c9cc67877-r2whn 0/1 ContainerCreating 0 0s

deployment-nginx-558dfc6f84-sjxn8 0/1 Terminating 0 56s

deployment-nginx-c9cc67877-r2whn 1/1 Running 0 1s

deployment-nginx-558dfc6f84-4zrgr 1/1 Terminating 0 77s

deployment-nginx-558dfc6f84-sjxn8 0/1 Terminating 0 57s

deployment-nginx-558dfc6f84-4zrgr 0/1 Terminating 0 78s

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pod -o yaml | grep "image: nginx"

- image: nginx:1.13

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl rollout history deployment deployment-nginx

deployment.apps/deployment-nginx

REVISION CHANGE-CAUSE

1 kubectl apply --filename=deployment-nginx-1.yaml --record=true

2 kubectl set image deployment deployment-nginx nginx=nginx:1.12 --record=true

3 kubectl set image deployment deployment-nginx nginx=nginx:1.13 --record=true

2번으로 롤백

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl rollout undo deployment deployment-nginx --to-revision=2

deployment.apps/deployment-nginx rolled back

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pod -o yaml | grep "image: nginx"

- image: nginx:1.12

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get replicasets.apps --show-labels

NAME DESIRED CURRENT READY AGE LABELS

deployment-nginx-558dfc6f84 3 3 3 2m41s app=cndk-nginx-pods,pod-template-hash=558dfc6f84

deployment-nginx-775869fd7 0 0 0 3m25s app=cndk-nginx-pods,pod-template-hash=775869fd7

deployment-nginx-c9cc67877 0 0 0 104s app=cndk-nginx-pods,pod-template-hash=c9cc67877

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pods,rs,deploy -o wide

NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES

pod/deployment-nginx-558dfc6f84-8cht4 1/1 Running 0 56s 10.244.0.53 10.0.10.80 <none> <none>

pod/deployment-nginx-558dfc6f84-tmrzg 1/1 Running 0 59s 10.244.0.161 10.0.10.141 <none> <none>

pod/deployment-nginx-558dfc6f84-zjz99 1/1 Running 0 58s 10.244.0.52 10.0.10.80 <none> <none>

NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR

replicaset.apps/deployment-nginx-558dfc6f84 3 3 3 3m23s nginx nginx:1.12 app=cndk-nginx-pods,pod-template-hash=558dfc6f84

replicaset.apps/deployment-nginx-775869fd7 0 0 0 4m7s nginx nginx:1.11 app=cndk-nginx-pods,pod-template-hash=775869fd7

replicaset.apps/deployment-nginx-c9cc67877 0 0 0 2m26s nginx nginx:1.13 app=cndk-nginx-pods,pod-template-hash=c9cc67877

NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR

deployment.apps/deployment-nginx 3/3 3 3 4m7s nginx nginx:1.12 app=cndk-nginx-pods

deployments.apps 삭제해야 지워 진다.

topasvga@cloudshell:~ (ap-seoul-1)$ kubectl delete deployments.apps --all

deployment.apps "deployment-nginx" deleted

감사합니다.

Master Seo 소속 클라우드전문가카페 직업 엔지니어

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