22 初始化容器 Init Container
kubectl get pods --all-namespaces -o wide
ssh node01
docker ps |grep liveness-exec
docker ps
k8s.gcr.io/pause-amd64.3.1 就是infra容器
docker ps |grep hrjr-web
docker ps
k8s.gcr.io/pause-amd64.3.1 就是infra容器
infra容器就是网络共享命名空间的容器
initpod1.yaml
---
apiVersion: v1
kind: Pod
metadata:
name: init-pod
labels:
app: init
spec:
initContainers:
- name: init-myservice
image: busybox
command: ['sh', '-c', 'unit nslookup myservice; do echo waiting for myservice; sleep 2; done;']
- name: init-mydb
image: busybox
command: ['sh','-c','until nslookup mydb; do echo waiting for mydb; sleep 2; done;']
containers:
- name: main-container
image: busybox
command: ['sh','-c', 'echo The app is running! && sleep 3600']
kubectl apply -f init-pod1.yaml
initservice.yaml
---
apiVersion: v1
kind: Service
metadata:
name: myservice
spec:
ports:
- protocol: TCP
port: 80
targetPort: 6379
kubectl create -f initservice.yaml
kubectl get pods
kubectl get svc
vi initservice.yaml
---
apiVersion: v1
kind: Service
metadata:
name: myservice
spec:
ports:
- protocol: TCP
port: 80
targetPort: 6379
---
apiVersion: v1
kind: Service
metadata:
name: mydb
spec:
ports:
- protocol: TCP
port: 80
targetPort: 6378
kubectl apply -f initservice.yaml
initconfig.yaml
---
apiVersion: v1
kind: Pod
metadata:
name: init-demo
labels:
app: init
spec:
initContainers:
- name: install
image: busybox
command:
- wget
- "-O"
- "/work-dir/index.html"
- http://www.baidu.com
volumeMounts:
- name: workdir
mountPath: /work-dir
containers:
- name: nginx
image: nginx
ports:
- containerPort: 80
volumeMounts:
- name: workdir
mountPath: /usr/share/nginx/html
volumes:
- name: workdir
emptyDir: {}
kubectl create -f initconfig.yaml
kubectl exec -it init-demo --/bin/bash
23 Replication Controller 与 Replica Set
RC && RS
rc-demo.yaml
---
apiVersion: v1
kind: ReplicationController
metadata:
name: rc-demo
labels:
app: rc
spec:
replicas: 3
template:
metadata:
labels:
app: rc
spec:
containers:
- name: nginx-demo
image: nginx
ports:
- containerPort: 80
kubectl create -f rc-demo.yaml
kubectl get replicationcontroller
简写：
kubectl get rc
kubectl describe rc rc-demo
kubectl get pods
修改副本数量为2个以后，更新rc-demo
kubectl apply -f rc-demo.yaml
kubectl edit rc rc-demo
dashboard 控制面板 scale 修改pod数量
在线升级nginx版本，滚动更新功能
kubectl rolling-update rc-demo --image=nginx:1.7.9
24 Deployment 的使用
deploy-demo.yaml
---
apiVersion: apps/v1beta1
kind: Deployment
metadata:
name: nginx-deploy
labels:
app: nginx-demo
spec:
replicas: 3
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
ports:
- containerPort: 80
kubectl get rs
---
apiVersion: apps/v1beta1
kind: Deployment
metadata:
name: nginx-deploy
labels:
app: nginx-demo
spec:
replicas: 3
minReadySeconds: 5 #5秒钟后更新
strategy:
type: RollingUpdate #滚动更新
rollingUpdate:
maxSurge: 1 #更新中 比原pod数最多多1个出来
maxUnavailable: 1 #更新中 最多允许1个pod不能提供服务
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx
ports:
- containerPort: 80
查看更新状态：
kubectl apply -f deploy-demo.yaml
kubectl rollout status deployment nginx-deploy 升级状态
kubectl rollout pause deployment nginx-deploy 暂停升级
kubectl rollout resume deployment nginx-deploy 恢复升级
kubectl get rs
kubectl get deployment
kubectl describe deployment nginx-deploy
kubectl rollout pause deployment nginx-deploy
kubectl rollout history deployment nginx-deploy 查看更新历史
kubectl apply -f deploy-demo.yaml --record=true 记录更新时使用的命令
---
apiVersion: apps/v1beta1
kind: Deployment
metadata:
name: nginx-deploy
labels:
app: nginx-demo
spec:
replicas: 3
revisionHistoryLimit: 15 #最小数量历史版本为 15个
minReadySeconds: 5 #5秒钟后更新
strategy:
type: RollingUpdate #滚动更新
rollingUpdate:
maxSurge: 1 #更新中 比原pod数最多多1个出来
maxUnavailable: 1 #更新中 最多允许1个pod不能提供服务
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx
ports:
- containerPort: 80
kubectl get rs
kubectl describe rs nginx-deploy-xxxyyy
Annotations: deployment.kubernetes.io/revision=2 即是历史版本
kubectl delete rs nginx-deploy-xxxyyy 删除pod
kubectl rollout history deployment nginx-deploy
回滚到上一个版本：
kubectl rollout undo deployment nginx-deploy
kubectl rollout status deployment nginx-deploy
kubectl get deployment nginx-deploy
kubectl get rs
kubectl get pods
kubectl describe pod nginx-deploy
回滚到指定版本： 修改 yaml 文件
回滚到 3 号版本：
kubectl rollout undo deployment nginx-deploy --to-revision=3
kubectl rollout history deployment nginx-deploy