目录
1. 简介
1.1 一些简单的入门小命令
2. pod基本操作
2.1 pod创建
2.2 pod删除,查看日志
3. service和deployment(控制器)
3.1 deployment基本操作
3.2 Pod扩容与缩容
3.3 expose暴露端口
3.3.1 ClusterIP默认类型暴露端口
3.3.2 NodePort类型暴露端口
3.4 更新pod镜像
3.5 回滚
3.6 删除
1. 简介
- Pod是可以创建和管理Kubernetes计算的最小可部署单元,一个Pod代表着集群中运行的一个进程,每个pod都有一个唯一的ip。 一个pod类似一个豌豆荚,包含一个或多个容器(通常是docker),多个容器间共享IPC、Network和UTC namespace。
1.1 一些简单的入门小命令
[root@server2 ~]# kubectl get pod ##获取pod
[root@server2 ~]# kubectl get ns ##查看namespace
NAME STATUS AGE
default Active 42h
kube-node-lease Active 42h
kube-public Active 42h
kube-system Active 42h
[root@server2 ~]# kubectl get pod -n kube-system ##查看相应namespace对应的pod,不加namespace就自动选择默认的namespace
NAME READY STATUS RESTARTS AGE
coredns-7f89b7bc75-4r9x6 1/1 Running 1 42h
coredns-7f89b7bc75-sxgkp 1/1 Running 1 42h
etcd-server2 1/1 Running 4 42h
kube-apiserver-server2 1/1 Running 3 42h
kube-controller-manager-server2 1/1 Running 3 42h
kube-flannel-ds-amd64-9m29g 1/1 Running 1 36h
kube-flannel-ds-amd64-c2rc7 1/1 Running 1 41h
kube-flannel-ds-amd64-xnb9p 1/1 Running 1 36h
kube-proxy-dlxmm 1/1 Running 1 36h
kube-proxy-mh677 1/1 Running 1 36h
kube-proxy-p87p4 1/1 Running 3 42h
kube-scheduler-server2 1/1 Running 4 42h
[root@server2 ~]# kubectl describe pod coredns-7f89b7bc75-4r9x6 -n kube-system ##如果出错可以使用这条命令来查看错误信息,要标明对应的namespace
[root@server2 ~]# kubectl delete pod cDoredns-7f89b7bc75-4r9x6 -n kube-system ##删除对应的pod
2. pod基本操作
2.1 pod创建
[root@server2 ~]# kubectl run -h ##查看创建pod帮助
[root@server2 ~]# kubectl run nginx --image=myapp:v1 ##创建一个pod应用,nginx是名字,myapp是景象
#--replicas=2 扩容参数 --record 记录参数
# kubectl run nginx --image=nginx --replicas=2 --record #参数使用方法
[root@server2 ~]# kubectl get pod ##查看pod
NAME READY STATUS RESTARTS AGE
nginx 1/1 Running 0 11s
[root@server2 ~]# kubectl get pod -n default ##查看指定namespace的节点
NAME READY STATUS RESTARTS AGE
nginx 1/1 Running 0 25s
[root@server2 ~]# kubectl get pod -o wide ##查看节点的具体信息
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx 1/1 Running 0 71s 10.244.2.3 server4 <none> <none>
[root@server2 ~]# kubectl run demo --image=busyboxplus -it ##交互式界面运行一个pod,ctrl+p+q退出可以通过kubectl attach demo -c demo -i -t重新进入
[root@server2 ~]# kubectl run demo --image=busyboxplus -it ##再次进入
2.2 pod删除,查看日志
[root@server2 ~]# kubectl delete pod nginx ##删除pod
pod "nginx" deleted
[root@server2 ~]# kubectl describe pod demo ##查看详细描述
[root@server2 ~]# kubectl logs demo ##查看日志
3. service和deployment(控制器)
3.1 deployment基本操作
[root@server2 ~]# kubectl create deployment nginx --image=myapp:v1 ##创建一个pod
deployment.apps/nginx created ##生成一个新的deployment控制器的pod,删除之后会自动重新生成不同id的pod
[root@server2 ~]# kubectl get all
NAME READY STATUS RESTARTS AGE
pod/demo 1/1 Running 0 70m
pod/nginx-67f9d9c97f-mb6zb 1/1 Running 0 13s ##id为mb6zb
[root@server2 ~]# kubectl delete pod nginx-67f9d9c97f-mb6zb ##删除pod后在查看
pod "nginx-67f9d9c97f-mb6zb" deleted
[root@server2 ~]# kubectl get pod ##生成新的id的pod
NAME READY STATUS RESTARTS AGE
demo 1/1 Running 0 73m
nginx-67f9d9c97f-4stvr 1/1 Running 0 16s
[root@server2 ~]# kubectl delete deployment nginx ##彻底删除deployment
[root@server2 ~]# kubectl get pod ##删除成功
NAME READY STATUS RESTARTS AGE
demo 1/1 Running 0 74m
3.2 Pod扩容与缩容
[root@server2 ~]# kubectl scale deployment --replicas=2 nginx
[root@server2 ~]# kubectl scale deployment nginx --replicas=2 ##两种书写方式都可以
deployment.apps/nginx scaled
[root@server2 ~]# kubectl get pod
NAME READY STATUS RESTARTS AGE
demo 1/1 Running 0 76m
nginx-67f9d9c97f-48gfz 1/1 Running 0 27s
nginx-67f9d9c97f-jh76r 1/1 Running 0 2s
[root@server2 ~]# kubectl scale deployment --replicas=4 nginx
deployment.apps/nginx scaled
[root@server2 ~]# kubectl get pod
NAME READY STATUS RESTARTS AGE
demo 1/1 Running 0 76m
nginx-67f9d9c97f-48gfz 1/1 Running 0 43s
nginx-67f9d9c97f-7gh4m 1/1 Running 0 3s
nginx-67f9d9c97f-hcd5z 1/1 Running 0 3s
nginx-67f9d9c97f-jh76r 1/1 Running 0 18s
3.3 expose暴露端口
- service是一个抽象概念,定义了一个服务的多个pod逻辑合集和访问pod的策略,一般把service称为微服务。- 创建service
$ kubectl expose deployment(控制器) nginx --port=80 --target-port=80
此时pod客户端可以通过service的名称访问后端的两个Pod
ClusterIP: 默认类型,自动分配一个仅集群内部可以访问的虚拟IP
- 使用NodePort类型暴露端口,让外部客户端访问Pod(即真机也可以访问)
$ kubectl edit svc nginx //修改service的type为NodePort
$ kubectl expose deployment nginx --port=80 --target-port=80 --type=NodePort //也可以在创建service时指定类型
NodePort: 在ClusterIP基础上为Service在每台机器上绑定一个端口,这样就可以通过 NodeIP:NodePort 来访问该服务
3.3.1 ClusterIP默认类型暴露端口
[root@server2 ~]# kubectl expose deployment nginx --port=80 ##ClusterIP默认类型暴露端口service/nginx exposed
[root@server2 ~]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 45h
nginx ClusterIP 10.104.139.148 <none> 80/TCP 9s
[root@server2 ~]# curl 10.104.139.148
Hello MyApp | Version: v1 | <a href="hostname.html">Pod Name</a>
[root@server2 ~]# curl 10.104.139.148/hostname.html
nginx-67f9d9c97f-48gfz
[root@server2 ~]# curl 10.104.139.148/hostname.html
nginx-67f9d9c97f-hcd5z
[root@server2 ~]# curl 10.104.139.148/hostname.html
nginx-67f9d9c97f-hcd5z
[root@server2 ~]# curl 10.104.139.148/hostname.html
nginx-67f9d9c97f-48gfz
[root@server2 ~]# kubectl describe svc nginx ##查看deployment详细信息
[root@server2 ~]# kubectl get pod -n kube-system -o wide ##查看namespace对应的所有pod详细信息
##server3和server4上同样可以访问到对应信息
[root@server3 ~]# curl 10.104.139.148/hostname.html
[root@server4 ~]# curl 10.104.139.148/hostname.html
3.3.2 NodePort类型暴露端口
[root@server2 ~]# kubectl get svc ##查看TYPENAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 45h
nginx ClusterIP 10.104.139.148 <none> 80/TCP 28m ##ClusterIP
[root@server2 ~]# kubectl edit svc nginx ##TYPE改成NodePort
[root@server2 ~]# kubectl get svc ##80映射31147端口
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 45h
nginx NodePort 10.104.139.148 <none> 80:31147/TCP 30m
##真机测试
[root@westos Desktop]# curl 172.25.13.2:31147
Hello MyApp | Version: v1 | <a href="hostname.html">Pod Name</a>
[root@westos Desktop]# curl 172.25.13.2:31147/hostname.html
nginx-67f9d9c97f-48gfz
[root@westos Desktop]# curl 172.25.13.2:31147/hostname.html
nginx-67f9d9c97f-48gfz
[root@westos Desktop]# curl 172.25.13.2:31147/hostname.html
nginx-67f9d9c97f-hcd5z
[root@westos Desktop]# curl 172.25.13.2:31147/hostname.html
nginx-67f9d9c97f-hcd5z
[root@westos Desktop]# curl 172.25.13.2:31147/hostname.html
nginx-67f9d9c97f-hcd5z
[root@westos Desktop]# curl 172.25.13.2:31147/hostname.html
nginx-67f9d9c97f-hcd5z
[root@westos Desktop]# curl 172.25.13.2:31147/hostname.html
nginx-67f9d9c97f-hcd5z
[root@westos Desktop]# curl 172.25.13.2:31147/hostname.html
3.4 更新pod镜像
[root@server2 ~]# kubectl set image deployment nginx myapp=myapp:v2 ##更新到v2[root@server2 ~]# kubectl rollout history deployment nginx ##查看更新记录
3.5 回滚
$ kubectl rollout history deployment nginx //查看历史版本$ kubectl rollout undo deployment nginx --to-revision=1 //回滚版本[root@server2 ~]# kubectl rollout history deployment nginx[root@server2 ~]# kubectl rollout undo deployment nginx --to-revision=1 ##回滚之前版本deployment.apps/nginx rolled back
[root@server2 ~]# kubectl rollout history deployment nginx
deployment.apps/nginx
REVISION CHANGE-CAUSE
2 <none>
3 <none>
[root@server2 ~]# kubectl get pod ##rs值变成版本1的rs值
NAME READY STATUS RESTARTS AGE
demo 1/1 Running 0 136m
nginx-67f9d9c97f-mv6n2 1/1 Running 0 22s
nginx-67f9d9c97f-zgpgh 1/1 Running 0 23s
[root@server2 ~]# kubectl describe deployments.apps nginx
3.6 删除