一、kubectl管理集群中deployment资源与service服务
1、相关参数
kubectl edit 编辑服务器侧资源
kubectl replace 替换，使用 yaml 配置文件来替换正在运行中的配置参数
kubectl patch 部分更新资源相关信息
kubectl apply 使用文件或者标准输入更改配置信息
kubectl scale 重新设定 Deployment/ReplicaSet/RC/Job 的 size
kubectl autoscale Deployment/ReplicaSet/RC 的自动扩展设定
kubectl cordon 设定 node 不可使用
kubectl uncordon 设定 node 可以使用
kubectl drain 设定 node 迚入维护模式
2、导入镜像
之前已经导入nginx镜像，直接操作，没有镜像可以自行在阿里云下载
二、编辑创建nginx-deployment.yaml /nginx-svc.yaml
1、创建deployment.yaml
vim nginx-deployment.yaml
[root@master ~]# vim nginx-deployment.yaml kind: Deployment apiVersion: extensions/v1beta1 metadata: name: nginx spec: replicas: 1 template: metadata: labels: name: nginx spec: containers: - name: nginx image: docker.io/nginx:latest imagePullPolicy: IfNotPresent ports: - containerPort: 80 protocol: TCP
2、创建servcie
vim nginx-svc.yaml
[root@master ~]# vim nginx-svc.yaml kind: Service apiVersion: v1 metadata: name: nginx labels: name: nginx spec: type: NodePort ports: - protocol: TCP nodePort: 31008 targetPort: 80 port: 80 selector: name: nginx
3、几个端口说明
nodePort:31008 #---后期用户可以通过node节点上这个端口访问nginx，公网接口
targetPort:80 #---指定nginx docker容器的端口
port:80 #---pod端口
4、create deployment/service
1）创建
kubectl create -f nginx-deployment.yaml
kubectl create -f nginx-svc.yaml
2）查看deployment/service/pod详细信息
kubectl get deploy
kubectl get svc
kubectl get pod -o wide
[root@master ~]# kubectl create -f nginx-deployment.yaml deployment "nginx" created [root@master ~]# kubectl create -f nginx-svc.yaml service "nginx" created [root@master ~]# kubectl get deploy NAME DESIRED CURRENT UP-TO-DATE AVAILABLE AGE mysql 1 1 1 1 1h nginx 1 1 1 1 26s [root@master ~]# kubectl get svc NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes 10.254.0.1 <none> 443/TCP 5d nginx 10.254.8.125 <nodes> 80:31008/TCP 24s [root@master ~]#
[root@master ~]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE mysql-1971774246-2f905 1/1 Running 0 1h 10.255.36.2 node2 nginx-1011335894-9wd5h 1/1 Running 0 2m 10.255.41.2 node1 [root@master ~]#
3）访问
上面已经知道pod运行在哪台节点及对外监听端口，接下来就是访问（上面标红字段）
4）通过其他节点访问nginx
虽然nginx是在node1上运行，但是通过其他节点也是可以访问，因为已经做负载均衡
三、kubectl edit命令
主要作用是修改service值
1、使用get -o参数指定输出消息为yaml类型
kubectl get service nginx -o yaml
[root@master ~]# kubectl get service nginx -o yaml apiVersion: v1 kind: Service metadata: creationTimestamp: 2019-11-03T20:45:43Z labels: name: nginx name: nginx namespace: default resourceVersion: "122656916" selfLink: /api/v1/namespaces/default/services/nginx uid: e7775727-fe7a-11e9-bc69-000c291c8b39 spec: clusterIP: 10.254.8.125 ports: - nodePort: 31008 port: 80 protocol: TCP targetPort: 80 selector: name: nginx sessionAffinity: None type: NodePort status: loadBalancer: {}
2、修改对外端口为31009
kubectl edit service nginx
和vim类似的操作
[root@master ~]# kubectl edit service nginx # Please edit the object below. Lines beginning with a '#' will be ignored, # and an empty file will abort the edit. If an error occurs while saving this file will be # reopened with the relevant failures. # apiVersion: v1 kind: Service metadata: creationTimestamp: 2019-11-03T20:45:43Z labels: name: nginx name: nginx namespace: default resourceVersion: "122656916" selfLink: /api/v1/namespaces/default/services/nginx uid: e7775727-fe7a-11e9-bc69-000c291c8b39 spec: clusterIP: 10.254.8.125 ports: - nodePort: 31009 port: 80 protocol: TCP targetPort: 80 selector: name: nginx sessionAffinity: None type: NodePort status: loadBalancer: {}
3、查看service，并验证
kubectl get service
[root@master ~]# kubectl get service NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes 10.254.0.1 <none> 443/TCP 5d nginx 10.254.8.125 <nodes> 80:31009/TCP 20m
访问web端
四、kubectl replace
replace 替换的意思
1、查看服务
kubectl get service
2、重定向一个nginx_replace的yaml文件
kubectl get service nginx -o yaml >nginx_replace.yaml
3、编辑，修改端口为31010
vim nginx_replace.yaml
4、执行替换
kubectl replace -f nginx_replace.yaml
5、检查service是否生效
kubectl get service
[root@master ~]# kubectl get service NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes 10.254.0.1 <none> 443/TCP 5d nginx 10.254.8.125 <nodes> 80:31009/TCP 20m [root@master ~]# kubectl get service nginx -o yaml >nginx_replace.yaml [root@master ~]# vim nginx_replace.yaml apiVersion: v1 kind: Service metadata: creationTimestamp: 2019-11-03T20:45:43Z labels: name: nginx name: nginx namespace: default resourceVersion: "123205401" selfLink: /api/v1/namespaces/default/services/nginx uid: e7775727-fe7a-11e9-bc69-000c291c8b39 spec: clusterIP: 10.254.8.125 ports: - nodePort: 31010 port: 80 protocol: TCP targetPort: 80 selector: name: nginx sessionAffinity: None type: NodePort status: loadBalancer: {} ~ ~ [root@master ~]# kubectl get service NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes 10.254.0.1 <none> 443/TCP 6d nginx 10.254.8.125 <nodes> 80:31010/TCP 17h ~
五、kubectl patch
当修改一部分配置时，使用patch会方便点，如pod换个image镜像
这里比如更换镜像使得nginx支持php
1、检查当前镜像是否支持php
kubectl exec -it nginx-1011335894-853ql bash
php
2、上传新镜像，并导入
这个可以在阿里云随便找一个
3、执行patch进行替换
kubectl patch pod nginx-1011335894-673bv -p '{"spec":{"containers":[{"name":"nginx","image":"docker.io/zxg/nginx-php-fpm56:latest"}]}}'
4、检查是否支持php
kubectl exec nginx-1011335894-853ql -it bash
[root@master ~]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE mysql-1971774246-jwrfc 1/1 Running 0 2h 10.255.41.5 node1 nginx-1011335894-853ql 1/1 Running 0 13s 10.255.36.2 node2 nginx-1011335894-pzgsj 1/1 Running 0 2h 10.255.41.2 node1 [root@master ~]# kubectl exec -it nginx-1011335894-853ql bash root@nginx-1011335894-853ql:/# nginx -v nginx version: nginx/1.13.7 root@nginx-1011335894-853ql:/# php bash: php: command not found root@nginx-1011335894-853ql:/# exit exit [root@master ~]# kubectl patch pod nginx-1011335894-853ql -p '{"spec":{"containers":[{"name":"nginx","image":"docker.io/zxg/nginx-php-fpm56:latest"}]}}' "nginx-1011335894-853ql" patched [root@master ~]# kubectl get pod NAME READY STATUS RESTARTS AGE mysql-1971774246-jwrfc 1/1 Running 0 2h nginx-1011335894-853ql 1/1 Running 1 3m nginx-1011335894-pzgsj 1/1 Running 0 2h [root@master ~]# kubectl exec nginx-1011335894-853ql -it bash bash-4.3# php -v PHP 5.6.32 (cli) (built: Dec 1 2017 19:58:36) Copyright (c) 1997-2016 The PHP Group Zend Engine v2.6.0, Copyright (c) 1998-2016 Zend Technologies with Zend OPcache v7.0.6-dev, Copyright (c) 1999-2016, by Zend Technologies
六、kubectl apply
是用来使用文件或者标准输入来更改配置信息
1、编辑svc.yaml文件
vim nginx-svc.yaml
改：nodePort:31010
为:nodePort:31011
2、执行apply命令
kubectl apply -f nginx-svc.yaml
3、检查结果
kubectl get svc
[root@master ~]# vim nginx-svc.yaml kind: Service apiVersion: v1 metadata: name: nginx labels: name: nginx spec: type: NodePort ports: - protocol: TCP nodePort: 31011 targetPort: 80 port: 80 selector: name: nginx [root@master ~]# kubectl apply -f nginx-svc.yaml service "nginx" configured [root@master ~]# kubectl get svc NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes 10.254.0.1 <none> 443/TCP 6d nginx 10.254.8.125 <nodes> 80:31011/TCP 23h [root@master ~]#
七、kubectl scale （规模）
用于横向扩展、是k8s或swarm这类容器编辑平台的重要功能之一
如这里把replica副本改为3
1、查看nginx运行在哪个节点
kubectl get pod -o wide
2、执行scale命令
kubectl scale --current-replicas=1 --replicas=3 deployment/nginx
3、再次查看nginx运行在哪个节点
kubectl get pod -o wide
[root@master ~]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE mysql-1971774246-2f905 1/1 Running 0 1d 10.255.36.2 node2 nginx-1011335894-9wd5h 1/1 Running 0 23h 10.255.41.2 node1 [root@master ~]# kubectl scale --current-replicas=1 --replicas=3 deployment/nginx deployment "nginx" scaled [root@master ~]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE mysql-1971774246-2f905 1/1 Running 0 1d 10.255.36.2 node2 nginx-1011335894-9wd5h 1/1 Running 0 23h 10.255.41.2 node1 nginx-1011335894-scm64 1/1 Running 0 5s 10.255.36.3 node2 nginx-1011335894-xtkqd 1/1 Running 0 5s 10.255.41.3 node1 [root@master ~]#
八、kubectl autoscale
用于自动扩展确认，跟scale不同的是前者还是需要手动执行，而autoscale则会根据负载进行调解，而这条命令可以对Deployment/ReplicaSet/RC进行设定，通过最小值和最大值的指定进行设定
1、设置最小2，最大5的自动设置
kubectl autoscale deployment nginx --min=2 --max=5
2、查看结果
应该是没变化，因为之前手动scale设置的3在这个2-5的区间
kubectl get pod -o wide
3、设置最小2，最大2
kubectl autoscale deployment nginx --min=2 --max=2
这里就报错了因为之前设置的是3
[root@master ~]# kubectl autoscale deployment nginx --min=2 --max=5 deployment "nginx" autoscaled [root@master ~]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE mysql-1971774246-2f905 1/1 Running 0 1d 10.255.36.2 node2 nginx-1011335894-9wd5h 1/1 Running 0 23h 10.255.41.2 node1 nginx-1011335894-scm64 1/1 Running 0 3m 10.255.36.3 node2 nginx-1011335894-xtkqd 1/1 Running 0 3m 10.255.41.3 node1 [root@master ~]# kubectl autoscale deployment nginx --min=2 --max=2 Error from server (AlreadyExists): horizontalpodautoscalers.autoscaling "nginx" already exists [root@master ~]#
九、kubectl cordon 与uncordon
如果其中一台node坏掉或者维护，暂时不能让生成的pod在此node上运行，需要通知kubernetes让其不要创建过来，就用cordon命令，如果uncordon就是取消这个设定
1、在node2上运行cordon命令
kubectl cordon node2
2、查看pod详情，没有变化
kubectl get pod -o wide
3、查看node详情
kubectl get nodes -o wide
发现node2状态为Ready,SchedulingDisabled
3、增加relicas副本
kubectl scale --replicas=6 deployment/nginx
4、再次查看pod详情
kubectl get pod -o wide
发现都是node1建立，node2已经封锁成功
5、使用uncordon取消cordon设定
kubectl uncordon node2
[root@master ~]# kubectl cordon node2 node "node2" cordoned [root@master ~]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE mysql-1971774246-2f905 1/1 Running 0 1d 10.255.36.2 node2 nginx-1011335894-9wd5h 1/1 Running 0 23h 10.255.41.2 node1 nginx-1011335894-scm64 1/1 Running 0 9m 10.255.36.3 node2 nginx-1011335894-xtkqd 1/1 Running 0 9m 10.255.41.3 node1 [root@master ~]# kubectl get nodes -o wide NAME STATUS AGE EXTERNAL-IP node1 Ready 6d <none> node2 Ready,SchedulingDisabled 5d <none> [root@master ~]# kubectl scale --replicas=6 deployment/nginx deployment "nginx" scaled [root@master ~]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE mysql-1971774246-2f905 1/1 Running 0 1d 10.255.36.2 node2 nginx-1011335894-7jvp0 1/1 Running 0 5s 10.255.41.5 node1 nginx-1011335894-8nd1q 1/1 Running 0 5s 10.255.41.6 node1 nginx-1011335894-9wd5h 1/1 Running 0 23h 10.255.41.2 node1 nginx-1011335894-lhtkm 1/1 Running 0 5s 10.255.41.4 node1 nginx-1011335894-scm64 1/1 Running 0 11m 10.255.36.3 node2 nginx-1011335894-xtkqd 1/1 Running 0 11m 10.255.41.3 node1 [root@master ~]#
[root@master ~]# kubectl uncordon node2 node "node2" uncordoned [root@master ~]# kubectl get node -o wide NAME STATUS AGE EXTERNAL-IP node1 Ready 6d <none> node2 Ready 5d <none> [root@master ~]#
十、kubectl drain （驱逐）
用于对某个node结点进行维护
1、drain两个作用：
1、设定此node不可以使用（cordon）
2、evict驱逐pod到他正常的node节点上
2、先删之前的nginx
kubectl delete deploy nginx
3、创建pod
kubectl create -f nginx-deployment.yaml
4、查看pod详情
kubectl get pod -o wide
5、执行drain命令 drain node2
kubectl drain node2
6、查看pod
get pod -o wide
镜像已经漂移过来了
7、查看node
node2状态为Ready,SchedulingDisabled ，完成配置
[root@master ~]# kubectl create -f nginx-deployment.yaml deployment "nginx" created [root@master ~]# kubectl scale --replicas=4 deployment nginx deployment "nginx" scaled [root@master ~]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE mysql-1971774246-2f905 1/1 Running 0 1d 10.255.36.2 node2 nginx-1011335894-4tpj5 1/1 Running 0 8s 10.255.41.3 node1 nginx-1011335894-673bv 1/1 Running 0 8s 10.255.36.3 node2 nginx-1011335894-hw8ld 1/1 Running 0 8s 10.255.36.4 node2 nginx-1011335894-pzgsj 1/1 Running 0 28s 10.255.41.2 node1 [root@master ~]# kubectl drain node2 node "node2" cordoned pod "nginx-1011335894-hw8ld" evicted pod "nginx-1011335894-673bv" evicted pod "mysql-1971774246-2f905" evicted node "node2" drained [root@master ~]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE mysql-1971774246-jwrfc 1/1 Running 0 7s 10.255.41.5 node1 nginx-1011335894-4tpj5 1/1 Running 0 1m 10.255.41.3 node1 nginx-1011335894-d683g 1/1 Running 0 7s 10.255.41.6 node1 nginx-1011335894-gs3lg 1/1 Running 0 7s 10.255.41.4 node1 nginx-1011335894-pzgsj 1/1 Running 0 1m 10.255.41.2 node1 [root@master ~]# get nodes -o wide
NAME STATUS AGE EXTERNAL-IP
node1 Ready 6d <none>
node2 Ready,SchedulingDisabled 5d <none>