by
Feb 15. 2023
1. 오라클 클라우드 - 쿠버네티스 -시작하기
<1> 쿠버네티스 시작하기
<2> pod 생성과 삭제
<3> deployment 삭제와 생성
<4> 개인 정리
<1> 쿠버네티스 시작하기
1
Oracle Cloud.
Cloud Shell로 쿠버네티스 사용해보자.
2
api-resources 보자
topasvga@cloudshell:~ (ap-seoul-1)$ kubectl api-resources
NAME SHORTNAMES APIVERSION NAMESPACED KIND
bindings v1 true Binding
componentstatuses cs v1 false :
:
clusterroles rbac.authorization.k8s.io/v1 false ClusterRole
rolebindings rbac.authorization.k8s.io/v1 true RoleBinding
roles rbac.authorization.k8s.io/v1 true Role
priorityclasses pc scheduling.k8s.io/v1 false PriorityClass
csidrivers storage.k8s.io/v1 false CSIDriver
csinodes storage.k8s.io/v1 false CSINode
csistoragecapacities storage.k8s.io/v1 true CSIStorageCapacity
storageclasses sc storage.k8s.io/v1 false StorageClass
volumeattachments storage.k8s.io/v1 false VolumeAttachment
3
네임 스페이스 보자.
디폴트 , kube-node, 퍼블릭, 시스템 이 있네요~
topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get namespaces
NAME STATUS AGE
default Active 17h
kube-node-lease Active 17h
kube-public Active 17h
kube-system Active 17h
4
만들어진 노드 보자.
워커 노드가 2개가 있다.
topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
10.0.10.141 Ready node 17h v1.25.4
10.0.10.80 Ready node 17h v1.25.4
5
클러스터 정보 보자~
topasvga@cloudshell:~ (ap-seoul-1)$ kubectl cluster-info
Kubernetes control plane is running at https://152.70.232.60:6443
CoreDNS is running at https://152.70.232.60:6443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy
To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.
6
노드 kube-system에 있는 파드를 보자~
topasvga@cloudshell:~ (ap-seoul-1)$ kubectl get pod -n kube-system
NAME READY STATUS RESTARTS AGE
coredns-6f5cb65d87-7xc4b 1/1 Running 0 17h
coredns-6f5cb65d87-x9wt5 1/1 Running 0 17h
csi-oci-node-8mnf4 1/1 Running 0 17h
csi-oci-node-h6f5j 1/1 Running 0 17h
kube-dns-autoscaler-6d666b855c-bmp42 1/1 Running 0 17h
kube-flannel-ds-9lnvp 1/1 Running 1 (17h ago) 17h
kube-flannel-ds-cc9mx 1/1 Running 1 (17h ago) 17h
kube-proxy-7ltz2 1/1 Running 0 17h
kube-proxy-tbf25 1/1 Running 0 17h
proxymux-client-bq95h 1/1 Running 0 17h
proxymux-client-vcszw 1/1 Running 0 17h
7
Prompt 변경 툴 설치 (선택)
topasvga@cloudshell:~ (ap-seoul-1)$ git clone https://github.com/jonmosco/kube-ps1.git
Cloning into 'kube-ps1'...
remote: Enumerating objects: 638, done.
remote: Counting objects: 100% (73/73), done.
remote: Compressing objects: 100% (48/48), done.
remote: Total 638 (delta 42), reused 52 (delta 25), pack-reused 565
Receiving objects: 100% (638/638), 7.25 MiB | 5.18 MiB/s, done.
Resolving deltas: 100% (336/336), done.
8
프롬프트 변경하기 (선택)
topasvga@cloudshell:~ (ap-seoul-1)$ vim .bashrc
topasvga@cloudshell:~ (ap-seoul-1)$ more .bashrc-backup
# .bashrc
# Source global definitions
if [ -f /etc/bashrc ]; then
. /etc/bashrc
fi
# Uncomment the following line if you don't like systemctl's auto-paging feature:
# export SYSTEMD_PAGER=
# User specific aliases and functions
source /etc/bashrc.cloudshell
9
변경
맨아래 source /etc/bashrc.cloudshell 대신
source ~/kube-ps1/kube-ps1.sh
PS1='[\u@\h:\w $(kube_ps1)]\$ '
KUBE_PS1_SYMBOL_ENABLE=false
topasvga@cloudshell:~ (ap-seoul-1)$ source ~/.bashrc
[topasvga@e752e0f6b962:~ (context-c2lqg34zlva:N/A)]$ sed -i "s/kubernetes-admin@kubernetes/kube/g" ~/.kube/config
[topasvga@e752e0f6b962:~ (context-c2lqg34zlva:N/A)]$ kubeoff
[topasvga@e752e0f6b962:~ ]$ kubeon
[topasvga@e752e0f6b962:~ (context-c2lqg34zlva:N/A)]$
[topasvga@e752e0f6b962:~ (context-c2lqg34zlva:N/A)]$ kubeoff
10
node 정보 보기
[topasvga@e752e0f6b962]$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
10.0.10.141 Ready node 17h v1.25.4
10.0.10.80 Ready node 17h v1.25.4
11
node정보 상세 보기
[topasvga@e752e0f6b962]$ kubectl get nodes -o wide
NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME
10.0.10.141 Ready node 17h v1.25.4 10.0.10.141 <none> Oracle Linux Server 8.6 5.4.17-2136.314.6.2.el8uek.x86_64 cri-o://1.25.1-111.el8
10.0.10.80 Ready node 17h v1.25.4 10.0.10.80 <none> Oracle Linux Server 8.6 5.4.17-2136.314.6.2.el8uek.x86_64 cri-o://1.25.1-111.el8
12
전체 pod 보기
[topasvga@e752e0f6b962]$ kubectl get pod --all-namespaces
NAMESPACE NAME READY STATUS RESTARTS AGE
default deployment-2048-8445476958-6w4nk 1/1 Running 0 8h
default deployment-2048-8445476958-tw72c 1/1 Running 0 8h
kube-system coredns-6f5cb65d87-7xc4b 1/1 Running 0 17h
kube-system coredns-6f5cb65d87-x9wt5 1/1 Running 0 17h
kube-system csi-oci-node-8mnf4 1/1 Running 0 17h
kube-system csi-oci-node-h6f5j 1/1 Running 0 17h
kube-system kube-dns-autoscaler-6d666b855c-bmp42 1/1 Running 0 17h
kube-system kube-flannel-ds-9lnvp 1/1 Running 1 (17h ago) 17h
kube-system kube-flannel-ds-cc9mx 1/1 Running 1 (17h ago) 17h
kube-system kube-proxy-7ltz2 1/1 Running 0 17h
kube-system kube-proxy-tbf25 1/1 Running 0 17h
kube-system proxymux-client-bq95h 1/1 Running 0 17h
kube-system proxymux-client-vcszw 1/1 Running 0 17h
<2> pod 생성과 삭제
1
기존 pod 확인
[topasvga@e752e0f6b962]$ kubectl get pod
NAME READY STATUS RESTARTS AGE
deployment-2048-8445476958-6w4nk 1/1 Running 0 8h
deployment-2048-8445476958-tw72c 1/1 Running 0 8h
2
nginx 이미지로 myweb1 pod 만들어보기
[topasvga@e752e0f6b962]$ kubectl run myweb1 --image nginx
pod/myweb1 created
[topasvga@e752e0f6b962]$ kubectl run myweb2 --image nginx && kubectl get pod -w
pod/myweb2 created
NAME READY STATUS RESTARTS AGE
deployment-2048-8445476958-6w4nk 1/1 Running 0 8h
deployment-2048-8445476958-tw72c 1/1 Running 0 8h
myweb1 1/1 Running 0 13s
myweb2 0/1 ContainerCreating 0 2s
myweb2 1/1 Running 0 12s
3
pod 보기
[topasvga@e752e0f6b962]$ kubectl get pod
NAME READY STATUS RESTARTS AGE
deployment-2048-8445476958-6w4nk 1/1 Running 0 8h
deployment-2048-8445476958-tw72c 1/1 Running 0 8h
myweb1 1/1 Running 0 37s
myweb2 1/1 Running 0 26s
4
pod 정보 상세 보기 - ip정보까지보기
[topasvga@e752e0f6b962]$ kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
deployment-2048-8445476958-6w4nk 1/1 Running 0 8h 10.244.0.4 10.0.10.80 <none> <none>
deployment-2048-8445476958-tw72c 1/1 Running 0 8h 10.244.0.132 10.0.10.141 <none> <none>
myweb1 1/1 Running 0 65s 10.244.0.5 10.0.10.80 <none> <none>
myweb2 1/1 Running 0 54s 10.244.0.133 10.0.10.141 <none> <none>
[topasvga@e752e0f6b962]$ ping 10.244.0.5
Ping is not supported in Cloud Shell
[topasvga@e752e0f6b962]$ curl 10.244.0.5
안됨
5
pod 지우기
[topasvga@e752e0f6b962]$ kubectl delete pod myweb1
pod "myweb1" deleted
[topasvga@e752e0f6b962]$ kubectl delete pod myweb2
pod "myweb2" deleted
<3> deployment 삭제와 생성
1
deployment 확인
[topasvga@e752e0f6b962]$ kubectl get deploy,replicasets,pods
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/deployment-2048 2/2 2 2 9h
NAME DESIRED CURRENT READY AGE
replicaset.apps/deployment-2048-8445476958 2 2 2 9h
NAME READY STATUS RESTARTS AGE
pod/deployment-2048-8445476958-6w4nk 1/1 Running 0 9h
pod/deployment-2048-8445476958-tw72c 1/1 Running 0 9h
2
삭제
[topasvga@e752e0f6b962]$ kubectl delete deploy deployment-2048
deployment.apps "deployment-2048" deleted
[topasvga@e752e0f6b962]$ kubectl get deploy,replicasets,pods
No resources found in default namespace.
3
커서 변경
[topasvga@e752e0f6b962:~ (context-c2lqg34zlva:N/A)]$ kubeoff
[topasvga@e752e0f6b962:~ ]$
[topasvga@e752e0f6b962:~ ]$
4
deployment 를 사용하는 이유를 알아보자.
원하는 상태를 유지한다.
[topasvga@e752e0f6b962:~ ]$ kubectl get pods
No resources found in default namespace.
5
deployment로 pod 3개를 만든다.
[topasvga@e752e0f6b962:~ ]$ kubectl create deployment my-webs --image=gcr.io/google-samples/kubernetes-bootcamp:v1 --replicas=3
deployment.apps/my-webs created
[topasvga@e752e0f6b962:~ ]$ kubectl get pods
NAME READY STATUS RESTARTS AGE
my-webs-6fc5987f47-hrr5r 0/1 ContainerCreating 0 5s
my-webs-6fc5987f47-kcztw 0/1 ContainerCreating 0 5s
my-webs-6fc5987f47-zm6ks 0/1 ContainerCreating 0 5s
6
상세히 보자
[topasvga@e752e0f6b962:~ ]$ kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
my-webs-6fc5987f47-hrr5r 1/1 Running 0 58s 10.244.0.6 10.0.10.80 <none> <none>
my-webs-6fc5987f47-kcztw 1/1 Running 0 58s 10.244.0.134 10.0.10.141 <none> <none>
my-webs-6fc5987f47-zm6ks 1/1 Running 0 58s 10.244.0.7 10.0.10.80 <none> <none>
7
6개 pod로 변경해 보자.
[topasvga@e752e0f6b962:~ ]$ kubectl scale --current-replicas=3 --replicas=6 deployment/my-webs
deployment.apps/my-webs scaled
[topasvga@e752e0f6b962:~ ]$ kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
my-webs-6fc5987f47-2p4kq 1/1 Running 0 3s 10.244.0.8 10.0.10.80 <none> <none>
my-webs-6fc5987f47-4xrc4 1/1 Running 0 3s 10.244.0.135 10.0.10.141 <none> <none>
my-webs-6fc5987f47-hrr5r 1/1 Running 0 83s 10.244.0.6 10.0.10.80 <none> <none>
my-webs-6fc5987f47-kcztw 1/1 Running 0 83s 10.244.0.134 10.0.10.141 <none> <none>
my-webs-6fc5987f47-mlwk6 1/1 Running 0 3s 10.244.0.136 10.0.10.141 <none><none>
my-webs-6fc5987f47-zm6ks 1/1 Running 0 83s 10.244.0.7 10.0.10.80 <none> <none>
8
Pod 1개를 지워보자~
[topasvga@e752e0f6b962:~ ]$ kubectl delete pod my-webs-6fc5987f47-2p4kq
pod "my-webs-6fc5987f47-2p4kq" deleted
[topasvga@e752e0f6b962:~ ]$ kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
my-webs-6fc5987f47-2p4kq 1/1 Terminating 0 71s 10.244.0.8 10.0.10.80 <none> <none>
my-webs-6fc5987f47-4xrc4 1/1 Running 0 71s 10.244.0.135 10.0.10.141 <none><none>
my-webs-6fc5987f47-hrr5r 1/1 Running 0 2m31s 10.244.0.6 10.0.10.80 <none> <none>
my-webs-6fc5987f47-kcztw 1/1 Running 0 2m31s 10.244.0.134 10.0.10.141 <none> <none>
my-webs-6fc5987f47-mlwk6 1/1 Running 0 71s 10.244.0.136 10.0.10.141 <none> <none>
my-webs-6fc5987f47-vfzlv 1/1 Running 0 17s 10.244.0.9 10.0.10.80 <none> <none>
my-webs-6fc5987f47-zm6ks 1/1 Running 0 31s 10.244.0.7 10.0.10.80 <none> <none>
8
pod 1개는 종료되었지만, 6개를 유지한다. 신규로 자동으로 1개가 생긴다.
[topasvga@e752e0f6b962:~ ]$ kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
my-webs-6fc5987f47-4xrc4 1/1 Running 0 88s 10.244.0.135 10.0.10.141 <none> <none>
my-webs-6fc5987f47-hrr5r 1/1 Running 0 2m48s 10.244.0.6 10.0.10.80 <none> <none>
my-webs-6fc5987f47-kcztw 1/1 Running 0 2m48s 10.244.0.134 10.0.10.141 <none> <none>
my-webs-6fc5987f47-mlwk6 1/1 Running 0 88s 10.244.0.136 10.0.10.141 <none> <none>
my-webs-6fc5987f47-vfzlv 1/1 Running 0 34s 10.244.0.9 10.0.10.80 <none> <none>
my-webs-6fc5987f47-zm6ks 1/1 Running 0 2m48s 10.244.0.7 10.0.10.80 <none> <none>
[topasvga@e752e0f6b962:~ ]$
9
pod를 1개로 줄여 보자
[topasvga@e752e0f6b962:~ ]$ kubectl scale --current-replicas=6 --replicas=1 deployment/my-webs
deployment.apps/my-webs scaled
5개는 종료 중이다.~
[topasvga@e752e0f6b962:~ ]$ kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
my-webs-6fc5987f47-4xrc4 1/1 Terminating 0 7m13s 10.244.0.135 10.0.10.141 <none> <none>
my-webs-6fc5987f47-hrr5r 1/1 Terminating 0 8m33s 10.244.0.6 10.0.10.80 <none> <none>
my-webs-6fc5987f47-kcztw 1/1 Terminating 0 8m33s 10.244.0.134 10.0.10.141 <none> <none>
my-webs-6fc5987f47-mlwk6 1/1 Running 0 7m13s 10.244.0.136 10.0.10.141 <none> <none>
my-webs-6fc5987f47-vfzlv 1/1 Terminating 0 6m19s 10.244.0.9 10.0.10.80 <none> <none>
my-webs-6fc5987f47-zm6ks 1/1 Terminating 0 8m33s 10.244.0.7 10.0.10.80 <none> <none>
Pod 5개가 종료 되었다.
원하는 데로 1개만 남았다.
[topasvga@e752e0f6b962:~ ]$ kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
my-webs-6fc5987f47-mlwk6 1/1 Running 0 7m42s 10.244.0.136 10.0.10.141 <none> <none>
10
모든 pod를 없애려면 어떻게 하나?
deploymentf를 지워야 한다.
[topasvga@e752e0f6b962:~ ]$ kubectl get deploy,pods
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/my-webs 3/3 3 3 32s
NAME READY STATUS RESTARTS AGE
pod/my-webs-6fc5987f47-mrqj4 1/1 Running 0 32s
pod/my-webs-6fc5987f47-nktzb 1/1 Running 0 32s
pod/my-webs-6fc5987f47-xfzdw 1/1 Running 0 32s
[topasvga@e752e0f6b962:~ ]$ kubectl delete deployments.apps my-webs
deployment.apps "my-webs" deleted
[topasvga@e752e0f6b962:~ ]$ kubectl get deploy,pods
No resources found in default namespace.
<4> 개인 정리
1
Oracle Cloud는 1달은 무료로 쿠버네티스 실습하기 좋다 ~
kubectl 명령어들이 잘 된다.
