第七章: Rolling Update
7.1 实践
修改deployment中app image版本
vim httpd.yml
apiVersion: apps/v1beta1
kind: Deployment
metadata:
name: httpd
spec:
replicas: 3
template:
metadata:
labels:
run: httpd
spec:
containers:
- name: httpd
image: httpd:2.2.31
ports:
- containerPort: 80
查看效果
kubectl describe deployment httpd
$kubectl apply -f httpd.yml
$kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
httpd-69cb5b9fdd-crtfm 1/1 Running 0 101m 10.244.3.118 k8s-node-122132073 <none> <none>
httpd-69cb5b9fdd-k9xbv 1/1 Running 0 101m 10.244.4.35 k8s-node-122132072 <none> <none>
httpd-6fdbf8b54-cnhdj 1/1 Running 0 34s 10.244.4.39 k8s-node-122132072 <none> <none>
httpd-6fdbf8b54-kgv2h 0/1 ContainerCreating 0 19s <none> k8s-node-122132073 <none> <none>
$ kubectl describe deployment httpd
NewReplicaSet: httpd-6fdbf8b54 (3/3 replicas created)
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal ScalingReplicaSet 97s deployment-controller Scaled up replica set httpd-6fdbf8b54 to 1
Normal ScalingReplicaSet 82s deployment-controller Scaled down replica set httpd-69cb5b9fdd to 2
Normal ScalingReplicaSet 82s deployment-controller Scaled up replica set httpd-6fdbf8b54 to 2
Normal ScalingReplicaSet 55s deployment-controller Scaled down replica set httpd-69cb5b9fdd to 1
Normal ScalingReplicaSet 55s deployment-controller Scaled up replica set httpd-6fdbf8b54 to 3
Normal ScalingReplicaSet 52s deployment-controller Scaled down replica set httpd-69cb5b9fdd to 0
7.2 回滚
布署时使用--record，然后就可以用--to-revision进行回滚。
httpd.v1.yml ~ httpd.v3.yml
三个文件的app image版本不同
vim httpd.v1.yml
kind: Deployment
metadata:
name: httpd
spec:
revisionHistoryLimit: 10
replicas: 3
template:
metadata:
labels:
run: httpd
spec:
containers:
- name: httpd
image: httpd:2.4.16
ports:
- containerPort: 80
布署服务
kubectl apply -f httpd.v1.yml --record # record的作用是将命令记录到revision记录中。
deployment.apps/httpd configured
$kubectl get deployment httpd -o wide
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
httpd 3/3 1 3 113m httpd httpd:2.4.16 run=httpd
$kubectl apply -f httpd.v2.yml --record
deployment.apps/httpd configured
$kubectl get deployment httpd -o wide
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
httpd 3/3 1 3 113m httpd httpd:2.4.17 run=httpd
$ kubectl apply -f httpd.v3.yml --record
$ kubectl get deployment httpd -o wide
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
httpd 3/3 1 3 116m httpd httpd:2.4.18 run=httpd
测试回滚
# 查看版本
$kubectl rollout history deployment
kubectl rollout history deployment
deployment.extensions/httpd
REVISION CHANGE-CAUSE
3 kubectl apply --filename=httpd.v1.yml --record=true
4 kubectl apply --filename=httpd.v2.yml --record=true
5 kubectl apply --filename=httpd.v3.yml --record=true
deployment.extensions/kubernetes-bootcamp
REVISION CHANGE-CAUSE
1 <none>
2 <none>
$kubectl describe deployment httpd
Image: httpd:2.4.18
#回滚
$kubectl rollout undo deployment httpd --to-revision=3
deployment.extensions/httpd rolled back
#检查效果
$kubectl describe deployment httpd
Image: httpd:2.4.16
