k8s用kubectl管理应用升级，服务发布与回滚，扩缩容

应用升级

Kubectl set image --help 有案例指定新版本，并添加标签，以便于回滚
[root@k8s-master ~]# kubectl set image deployment/nginx nginx=nginx:1.11 --record
升级之后他会将所有版本进行替换，用describe来查看版本
[root@k8s-master ~]# kubectl get pods
NAME READY STATUS RESTARTS AGE
busybox-5d4f595646-dzjv4 1/1 Running 0 2d
nginx-76c4c6d6d8-5w825 1/1 Running 0 2m
nginx-76c4c6d6d8-bh2sm 1/1 Running 0 2m
nginx-76c4c6d6d8-cwhw5 1/1 Running 0 1m

用describe来查看版本，看到版本已经升级为1.11版本了，另外下面还有他的输出信息
[root@k8s-master ~]# kubectl describe po/nginx-76c4c6d6d8-cwhw5
nginx:
Container ID: docker://ca046dd27d86bc10f330131be7ba5b91b14cb555c5d9677bb23f481e4e69aa67
Image: nginx:1.11

第二种修改应用版本===可以使用edit
直接进行编辑就行
[root@k8s-master ~]# kubectl edit deploy/nginx
找到image直接修改进行保存，升级之后他会将所有版本进行替换，用describe来查看版本

等启动之后查看pod重启新的镜像已经运行了
[root@k8s-master ~]# kubectl get pods
NAME READY STATUS RESTARTS AGE
busybox-5d4f595646-dzjv4 1/1 Running 0 2d
nginx-7454cd89d8-fpncj 1/1 Running 0 5m
nginx-7454cd89d8-gdz8c 1/1 Running 0 4m
nginx-7454cd89d8-tlngj 1/1 Running 0 5m
用describe查看Pod镜像信息
[root@k8s-master ~]# kubectl describe po/nginx-7454cd89d8-tlngj
nginx:
Container ID: docker://6768df2391defe44097e3ce2a857529ec614d49962181c1cf541c1bbc6dbce08
Image: nginx:1.15

用node端直接访问查看版本
[root@k8s-node1 ~]# curl -I 10.10.10.173:88
HTTP/1.1 200 OK
Server: nginx/1.15.12
Date: Mon, 08 Jul 2019 04:23:42 GMT

查看版本升级信息
[root@k8s-master ~]# kubectl rollout history deploy/nginx
deployments “nginx”
REVISION CHANGE-CAUSE
1
2
3

记录版本信息状态，便于回滚

[root@k8s-master ~]# kubectl set image deployment/nginx nginx=nginx:1.16 --record
[root@k8s-master ~]# kubectl rollout history deploy/nginx
deployments “nginx”
REVISION CHANGE-CAUSE
1
2
3
4 kubectl set image deployment/nginx nginx=nginx:1.16 --record=true
进行回滚用rollout undo，默认恢复到上一个版本也就是1.15
[root@k8s-master ~]# kubectl rollout undo deploy/nginx
默认少一个3,也就是回到上次第三次版本了
[root@k8s-master ~]# kubectl rollout history deploy/nginx
deployments “nginx”
REVISION CHANGE-CAUSE
1
2
4 kubectl set image deployment/nginx nginx=nginx:1.16 --record=true
5
[root@k8s-master ~]# kubectl describe po/nginx-7454cd89d8-txjpm
Containers:
nginx:
Container ID: docker://f17b88c301d61b8c75a46cba84d97c285f5d61886c081b3cfc9c0668e5cbf4e3
Image: nginx:1.15

业务量突然增加，我们需要增加副本

[root@k8s-master ~]# kubectl scale deploy/nginx --replicas=10
deployment “nginx” scaled
[root@k8s-master ~]# kubectl get pod
NAME READY STATUS RESTARTS AGE
busybox-5d4f595646-dzjv4 1/1 Running 0 2d
nginx-7454cd89d8-4cct8 1/1 Running 0 19s
nginx-7454cd89d8-75tvg 1/1 Running 0 7m
nginx-7454cd89d8-7v5qp 1/1 Running 0 1m
nginx-7454cd89d8-dtsgq 1/1 Running 0 19s
nginx-7454cd89d8-hjcpw 1/1 Running 0 7m
nginx-7454cd89d8-mhhww 1/1 Running 0 19s
nginx-7454cd89d8-txjpm 1/1 Running 0 7m
nginx-7454cd89d8-vkmjn 1/1 Running 0 19s
nginx-7454cd89d8-z8dbn 1/1 Running 0 19s
nginx-7454cd89d8-zn8pm 1/1 Running 0 1m

业务量下降我们进行缩容

[root@k8s-master ~]# kubectl scale deploy/nginx --replicas=5
[root@k8s-master ~]# kubectl get pod
NAME READY STATUS RESTARTS AGE
busybox-5d4f595646-dzjv4 1/1 Running 0 2d
nginx-7454cd89d8-75tvg 1/1 Running 0 8m
nginx-7454cd89d8-7v5qp 1/1 Running 0 3m
nginx-7454cd89d8-hjcpw 1/1 Running 0 8m
nginx-7454cd89d8-txjpm 1/1 Running 0 8m
nginx-7454cd89d8-zn8pm 1/1 Running 0 3m
要是不需要这些资源或者换项目了
直接用delete=======删除deploy还有service
[root@k8s-master ~]# kubectl delete deploy/nginx
deployment “nginx” deleted
[root@k8s-master ~]# kubectl delete svc/nginx-service
查看资源已经删除
[root@k8s-master ~]# kubectl get all