一、标签是k8s特色的管理方式，便于分类管理资源对象。一个标签可以对应多个资源，一个资源也可以有多个标签，它们是多对多的关系。 一个资源拥有多个标签，可以实现不同维度的管理。
1.查看标签
[root@k8s-master1 demo]# kubectl get pods --show-labels NAME READY STATUS RESTARTS AGE LABELS centos-78656cf799-g5zl7 1/1 Running 3 39h pod-template-hash=78656cf799,run=centos jenkins-0 0/1 Running 3 39h controller-revision-hash=jenkins-5969f94b88,name=jenkins,statefulset.kubernetes.io/pod-name=jenkins-0 nfs-client-provisioner-6998d9d457-jdmdf 1/1 Running 4 40h app=nfs-client-provisioner,pod-template-hash=6998d9d457 [root@k8s-master1 demo]# kubectl get node --show-labels NAME STATUS ROLES AGE VERSION LABELS 192.168.1.112 Ready <none> 13d v1.12.1 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=192.168.1.112 192.168.1.113 Ready <none> 13d v1.12.1 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=192.168.1.113
2.过滤标签
[root@k8s-master1 demo]# kubectl get pods -l app NAME READY STATUS RESTARTS AGE nfs-client-provisioner-6998d9d457-jdmdf 1/1 Running 4 40h [root@k8s-master1 demo]# kubectl get pods -L app NAME READY STATUS RESTARTS AGE APP centos-78656cf799-g5zl7 1/1 Running 3 39h jenkins-0 0/1 Running 3 39h nfs-client-provisioner-6998d9d457-jdmdf 1/1 Running 4 40h nfs-client-provisioner
3.增加标签，修改标签
[root@k8s-master1 demo]# kubectl label pod jenkins-0 app=jenkins-0 --overwrite pod/jenkins-0 labeled [root@k8s-master1 demo]# kubectl get pods -L app NAME READY STATUS RESTARTS AGE APP centos-78656cf799-g5zl7 1/1 Running 3 39h jenkins-0 0/1 Running 3 39h jenkins-0 nfs-client-provisioner-6998d9d457-jdmdf 1/1 Running 4 40h nfs-client-provisioner