Kubernetes3-kubectl管理Kubernetes容器平台-2

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)

      http://192.168.216.53:31008/

 

    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

      http://192.168.216.54:31009/

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>

 

 

转载请注明出处:https://www.cnblogs.com/zhangxingeng/p/11807083.html

 

 

posted @ 2019-11-07 18:52  乐章  阅读(643)  评论(0编辑  收藏  举报