滚动升级回滚
ReplicationController
资源文件
apiVersion: v1
kind: ReplicationController
metadata:
name: kubia-v1
labels:
app: kubia
spec:
replicas: 3
template:
metadata:
name: kubia
labels:
app: kubia
spec:
containers:
- image: luksa/kubia:v1
name: nodejes
---
apiVersion: v1
kind: Service
metadata:
name: kubia
spec:
type: LoadBalancer
ports:
- port: 80
targetPort: 8080
selector:
app: kubia
apply资源到K8S
kubectl create namespace update-rollback
kubectl apply -f kubia-v1.yaml -n update-rollback
通过暴露端口访问资源
curl http://暴露地址
执行滚动升级指令
kubectl rolling-update kubia-v1 kubia-v2 --image=luksa/kubia:v2 -n update-rollback
Deployment
资源文件
apiVersion: apps/v1
kind: Deployment
metadata:
name: kubia
labels:
app: kubia
spec:
replicas: 3
selector:
matchLabels:
app: kubia
template:
metadata:
name: kubia
labels:
app: kubia
spec:
containers:
- image: luksa/kubia:v1
name: nodejes
---
apiVersion: v1
kind: Service
metadata:
name: kubia
spec:
type: LoadBalancer
ports:
- port: 80
targetPort: 8080
selector:
app: kubia
apply资源到K8S
kubectl create namespace update-rollback
kubectl apply -f kubia.yaml -n update-rollback
通过暴露端口访问资源
curl http://暴露地址
修改镜像版本触发滚动升级到v2
apiVersion: apps/v1
kind: Deployment
metadata:
name: kubia
labels:
app: kubia
spec:
replicas: 3
minReadySeconds: 10
selector:
matchLabels:
app: kubia
template:
metadata:
name: kubia
labels:
app: kubia
spec:
containers:
- image: luksa/kubia:v2
name: nodejes
---
apiVersion: v1
kind: Service
metadata:
name: kubia
spec:
type: LoadBalancer
ports:
- port: 80
targetPort: 8080
selector:
app: kubia
-
minReadySeconds：表示新创建pod至少要成功运行多久之后才能视为可用
-
通过strategy属性可以设置升级的方式。默认为滚动升级（RollingUpdate），另一种为删除所有旧Pod再创建新pod(Recreate)
-
maxSurge：允许超出期望副本数的百分比的pod数量。也可以直接指定个数，默认值为1
-
maxUnavailable：允许不可用pod占期望副本数的百分比。也可以直接指定个数，默认值为1
-
spec:
strategy:
rollingUpdate:
maxSurge: 1
maxUnavailable: 1
type: RollingUpdate
修改镜像版本触发滚动升级到v3
apiVersion: apps/v1
kind: Deployment
metadata:
name: kubia
labels:
app: kubia
spec:
replicas: 3
minReadySeconds: 10
selector:
matchLabels:
app: kubia
template:
metadata:
name: kubia
labels:
app: kubia
spec:
containers:
- image: luksa/kubia:v3
name: nodejes
---
apiVersion: v1
kind: Service
metadata:
name: kubia
spec:
type: LoadBalancer
ports:
- port: 80
targetPort: 8080
selector:
app: kubia
查看历史版本
kubectl rollout history deployment kubia -n update-rollback
回滚到上一个版本
kubectl rollout undo deployment kubia -n update-rollback
- rollout命令适用于deployments、daemonsets、statefulsets
回滚到指定版本
kubectl rollout undo deployment kubia --to-revision=1 -n update-rollback
限制历史版本数量
通过revisionHistoryLimit可以限制历史版本的数量，默认为10
spec:
revisionHistoryLimit: 10
暂停滚动升级
kubectl rollout pause deployment kubia -n update-rollback
恢复滚动升级
kubectl rollout resume deployment kubia -n update-rollback
使用就绪探针阻止问题版本滚动升级
apiVersion: apps/v1
kind: Deployment
metadata:
name: kubia
labels:
app: kubia
spec:
replicas: 3
minReadySeconds: 10
strategy:
rollingUpdate:
maxSurge: 1
maxUnavailable: 0
type: RollingUpdate
selector:
matchLabels:
app: kubia
template:
metadata:
name: kubia
labels:
app: kubia
spec:
containers:
- image: luksa/kubia:v3
name: nodejes
readinessProbe:
periodSeconds: 1
httpGet:
path: /
port: 8080
---
apiVersion: v1
kind: Service
metadata:
name: kubia
spec:
type: LoadBalancer
ports:
- port: 80
targetPort: 8080
selector:
app: kubia
- maxUnavailable为0，maxSurge为1：保证pod一个一个被替换
- 就绪探针检测pod是否正真可访问
查看升级状态
查看升级状态可以发现升级流程一直没有继续下去
kubectl rollout status deployment kubia -n update-rollback
查看pod情况
查看pod情况可以看到pod一直没到就绪状态，应该就绪探针检测到异常
kubectl get pods -n update-rollback
取消出错版本滚动升级
kubectl rollout undo deployment kubia -n update-rollback
Helm
查看Release列表
helm list -n aim-upgrade-test2
查看Release历史版本
helm history devops-wuvreb-register -n aim-upgrade-test2
回滚Release到历史版本
回滚到指定版本
helm rollback devops-wuvreb-register 2 -n aim-upgrade-test2
查看release状态
helm status devops-wuvreb-register --show-desc -n aim-upgrade-test2
