1.增加节点标签 备注 =：代表增加标签
kubectl label nodes node3 node-role.kubernetes.io/node3=
2.减少节点标签 备注 -：代表减少标签
kubectl label nodes node3 node-role.kubernetes.io/node3-
在某些特殊情况下，需要将某些服务固定在一台宿主机上, k8s可以使用label给node节点打上标签来满足这种需求.
Label添加删除和修改
添加label
# 语法
kubectl label nodes <node-name> <label-key>=<label-value>
# 查看现有node及label
[root@master ~]# kubectl get nodes --show-labels
NAME STATUS ROLES AGE VERSION LABELS
master Ready master 54d v1.13.4 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=master,node-role.kubernetes.io/master=
node01 Ready <none> 54d v1.13.4 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=node01
node02 Ready <none> 6d19h v1.13.4 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=node02
# 添加一个key为disktype和value为ssd的label
[root@master ~]# kubectl label nodes node01 disktype=ssd
node/node01 labeled
# 查看是否被添加
[root@master ~]# kubectl get nodes --show-labels
NAME STATUS ROLES AGE VERSION LABELS
master Ready master 54d v1.13.4 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=master,node-role.kubernetes.io/master=
node01 Ready <none> 54d v1.13.4 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,disktype=ssd,kubernetes.io/hostname=node01
删除Label
# 语法
kubectl label nodes <node-name> <label-key>-
# 删除key为disktype的label
[root@master ~]# kubectl label nodes node01 disktype-
node/node01 labeled
[root@master ~]# kubectl get nodes --show-labels
NAME STATUS ROLES AGE VERSION LABELS
master Ready master 54d v1.13.4 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=master,node-role.kubernetes.io/master=
node01 Ready <none> 54d v1.13.4 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=node01
node02 Ready <none> 6d19h v1.13.4 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=node02
修改Label的值，
#语法: 需要加上--overwrite参数：
kubectl label nodes <node-name> <label-key>=<label-value> --overwrite
[root@master ~]# kubectl label nodes node01 disktype=ssd
node/node01 labeled
[root@master ~]# kubectl label nodes node01 disktype=hdd --overwrite
node/node01 labeled
[root@master ~]# kubectl get nodes --show-labels
NAME STATUS ROLES AGE VERSION LABELS
master Ready master 54d v1.13.4 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=master,node-role.kubernetes.io/master=
node01 Ready <none> 54d v1.13.4 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,disktype=hdd,kubernetes.io/hostname=node01
node02 Ready <none> 6d19h v1.13.4 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=node02
Pod选择Label
# 添加nodeSelector选项用来选择对应的node
apiVersion: v1
kind: Pod
metadata:
name: nginx
labels:
env: test
spec:
containers:
- name: nginx
image: nginx
imagePullPolicy: IfNotPresent
nodeSelector:
disktype: ssd