深入学习Kubernetes(七)：kubectl命令用法
语法：
kubectl [command] [TYPE] [NAME] [flags] 1 command：子命令，用于操作Kubernetes集群资源对象的命令，如create, delete, describe, get, apply等 2 TYPE：资源对象的类型，如pod, service, rc, deployment, node等，可以单数、复数以及简写（pod, pods, po/service, services, svc） 3 NAME：资源对象的名称，不指定则返回所有，如get pod 会返回所有pod， get pod nginx， 只返回nginx这个pod 4 flags：kubectl子命令的可选参数，例如-n 指定namespace，-s 指定apiserver的URL
资源对象类型列表 可以用这个命令获取到：
[root@marster1 ~]# kubectl api-resources NAME SHORTNAMES APIGROUP NAMESPACED KIND bindings true Binding componentstatuses cs false ComponentStatus configmaps cm true ConfigMap endpoints ep true Endpoints events ev true Event limitranges limits true LimitRange namespaces ns false Namespace nodes no false Node persistentvolumeclaims pvc true PersistentVolumeClaim persistentvolumes pv false PersistentVolume pods po true Pod podtemplates true PodTemplate replicationcontrollers rc true ReplicationController resourcequotas quota true ResourceQuota secrets true Secret serviceaccounts sa true ServiceAccount services svc true Service mutatingwebhookconfigurations admissionregistration.k8s.io false MutatingWebhookConfiguration validatingwebhookconfigurations admissionregistration.k8s.io false ValidatingWebhookConfiguration customresourcedefinitions crd,crds apiextensions.k8s.io false CustomResourceDefinition apiservices apiregistration.k8s.io false APIService controllerrevisions apps true ControllerRevision daemonsets ds apps true DaemonSet deployments deploy apps true Deployment replicasets rs apps true ReplicaSet statefulsets sts apps true StatefulSet tokenreviews authentication.k8s.io false TokenReview localsubjectaccessreviews authorization.k8s.io true LocalSubjectAccessReview selfsubjectaccessreviews authorization.k8s.io false SelfSubjectAccessReview selfsubjectrulesreviews authorization.k8s.io false SelfSubjectRulesReview subjectaccessreviews authorization.k8s.io false SubjectAccessReview horizontalpodautoscalers hpa autoscaling true HorizontalPodAutoscaler cronjobs cj batch true CronJob jobs batch true Job certificatesigningrequests csr certificates.k8s.io false CertificateSigningRequest events ev events.k8s.io true Event daemonsets ds extensions true DaemonSet deployments deploy extensions true Deployment ingresses ing extensions true Ingress networkpolicies netpol extensions true NetworkPolicy podsecuritypolicies psp extensions false PodSecurityPolicy replicasets rs extensions true ReplicaSet nodes metrics.k8s.io false NodeMetrics pods metrics.k8s.io true PodMetrics networkpolicies netpol networking.k8s.io true NetworkPolicy poddisruptionbudgets pdb policy true PodDisruptionBudget podsecuritypolicies psp policy false PodSecurityPolicy clusterrolebindings rbac.authorization.k8s.io false ClusterRoleBinding clusterroles rbac.authorization.k8s.io false ClusterRole rolebindings rbac.authorization.k8s.io true RoleBinding roles rbac.authorization.k8s.io true Role priorityclasses pc scheduling.k8s.io false PriorityClass storageclasses sc storage.k8s.io false StorageClass volumeattachments storage.k8s.io false VolumeAttachment
- 这个命令也可获取到 kubectl explain
特殊用法：
##同时查看多个pod [root@marster1 ~]# kubectl get pods dz-mysql-77c6c66578-fzdd2 dz-web-648dcfbfc9-68wwf NAME READY STATUS RESTARTS AGE dz-mysql-77c6c66578-fzdd2 1/1 Running 1 11h NAME READY STATUS RESTARTS AGE dz-web-648dcfbfc9-68wwf 1/1 Running 1 11h ## 查看pod同时查看deploy [root@marster1 ~]# kubectl get pods/dz-mysql-77c6c66578-fzdd2 deploy/dz-web NAME READY STATUS RESTARTS AGE pod/dz-mysql-77c6c66578-fzdd2 1/1 Running 1 11h NAME DESIRED CURRENT UP-TO-DATE AVAILABLE AGE deployment.extensions/dz-web 1 1 1 1 11h ##同时创建不同资源对象 kubectl create -f pod1.yaml -f rc1.yaml -f service1.yaml
kubectl子命令：主要包括对资源的创建、删除、查看、修改、配置、运行等
查看kubectl所有子命令：
#kubectl --help
查看kubectl支持的参数:
#kubectl options
kubectl输出格式:kubectl命令可以用多种格式对结果进行显示，输出格式通过-o参数指定
-o支持的格式有:
实例：
##能查看到pod在那个node节点上创建 [root@marster1 ~]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE dz-mysql-77c6c66578-fzdd2 1/1 Running 2 2d 172.20.2.37 192.168.0.112 <none> [root@marster1 ~]#kubectl get pod -o yaml [root@marster1 ~]#kubectl get pod -o custom-columns=NAME:.metadata.name,RESC:.metadata.resourceVersion NAME RESC dz-mysql-77c6c66578-fzdd2 107255 dz-web-648dcfbfc9-68wwf 108898 mysql-665554f76b-27qc8 108698 nginx-6f858d4d45-jpjgg 107030 [root@marster1 ~]#kubectl get pod --sort-by=.metadata.name //按name排序 NAME READY STATUS RESTARTS AGE dz-mysql-77c6c66578-fzdd2 1/1 Running 2 2d dz-web-648dcfbfc9-68wwf 0/1 ImagePullBackOff 1 2d mysql-665554f76b-27qc8 0/1 CrashLoopBackOff 55 2d nginx-6f858d4d45-jpjgg 1/1 Running 3 2d
kubectl命令示例：
1.创建资源对象
1.1根据yaml文件创建service和deployment
#kubectl create -f my-service.yaml -f my-deploy.yaml
1.2可以指定一个目录，这样可以一次性根据该目录下所有yaml或json文件定义资源
#kubectl create -f <directory>
2.查看资源对象
2.1查看所有pod
#kubectl get pods
2.2查看deployment和service
#kubectl get deploy,svc
3.描述资源对象
3.1显示node的详细信息
#kubectl describe nodes <node-name>
3.2显示pod的详细信息
#kubectl describe pods/<pod-name>
3.3显示deployment管理的pod信息
#kubectl describe pods <deployment-name>
4.删除资源对象
4.1基于yaml文件删除
#kubectl delete -f pod.yaml
4.2删除所有pod
#kubectl delete po --all
5.执行容器的命令
5.1在pod中执行某个命令，如date
kubectl exec <pod-name> date //pod-name如果不加，默认会选择第一个pod
5.2指定pod的某个容器执行命令
kubectl exec <pod-name> date
5.3进入到pod的容器里
kubectl exec -it <pod-name> bash
6 查看容器日志
kubectl logs <pod-name>
可以动态查看，类似于tail -f
kubectl logs -f <pod-name> -c <container-name>
