污点和容忍度

未分类 2年前 0 16

taints是键值数据，用在pod上

[root@master01 ~]# kubectl describe nodes master01
Taints:             node-role.kubernetes.io/master:NoSchedule

NoSchedule:

仅影响pod调度过程，当pod能容忍这个节点污点

NoExecute：

既影响调度过程，又影响现存的pod对象，如果存在的pod不能容忍节点后来加的污点，这个pod就会被驱逐。

PreferNoSchedule：

最好不，也可以，是NoSchedule的柔性版本

在pod对象定义容忍度的时候

管理节点污点

# Update node 'foo' with a taint with key 'dedicated' and value 'special-user' and effect 'NoSchedule'.
# If a taint with that key and effect already exists, its value is replaced as specified.
kubectl taint nodes foo dedicated=special-user:NoSchedule

# Remove from node 'foo' the taint with key 'dedicated' and effect 'NoSchedule' if one exists.
kubectl taint nodes foo dedicated:NoSchedule-

# Remove from node 'foo' all the taints with key 'dedicated'
kubectl taint nodes foo dedicated-

# Add a taint with key 'dedicated' on nodes having label mylabel=X
kubectl taint node -l myLabel=X dedicated=foo:PreferNoSchedule

# Add to node 'foo' a taint with key 'bar' and no value
kubectl taint nodes foo bar:NoSchedule

示例：

[root@master01 ~]# kubectl taint node node02 node-type=production:NoSchedule
node/node02 tainted

创建一个pod

[root@master01 yaml]# cat pod-taint.yaml 
apiVersion: v1
kind: Pod
metadata:
  name: taint-pod
  namespace: default
  labels:
    tomcat:  tomcat-pod
spec:
  containers:
  - name:  taint-pod
    ports:
    - containerPort: 8080
    image: tomcat:8.5-jre8-alpine
    imagePullPolicy: IfNotPresent

创建，不会调度到node02上了，因为没有定义容忍度

[root@master01 yaml]# kubectl apply -f pod-taint.yaml

把node01也打上污点

[root@master01 yaml]# kubectl taint node node01 node-type=dev:NoExecute
node/node01 tainted

可以看到node01节点上的pod都被删除了

创建yaml文件

[root@master01 yaml]# cat pod-demo-1.yaml 
apiVersion: v1
kind: Pod
metadata:
  name: myapp-deploy
  namespace: default
  labels:
    app: myapp
    release: canary
spec:
      containers:
      - name: myapp
        image: ikubernetes/myapp:v1
        ports:
        - name: http
          containerPort: 80
      tolerations:
      - key: "node-type"
        operator: "Equal"
        value: "production"
        effect: "NoSchedule"

[root@master01 yaml]# kubectl apply -f pod-demo-1.yaml 
pod/myapp-deploy created

删除污点

[root@master01 yaml]# kubectl taint nodes node01 node-type-
node/node01 untainted
[root@master01 yaml]# kubectl taint nodes node02 node-type-
node/node02 untainted