Taints和Tolerations一起工作以确保不将pod安排到不适当的节点上
将一个或多个污点应用于节点;，这标志着节点不应该接受任何不能容忍污点的pod
Tolerations允许（但不要求）pods调度到具有匹配的污点的节点上
**

污点

设置污点

kubectl taint node node01 node-role.kubernetes.io/node=:NoSchedule

取消污点

kubectl taint node node01 node-role.kubernetes.io/node:NoSchedule-
检查污点
kubectl describe nodes node01

Taintseffect可以定义为：
NoSchedule 表示不允许调度，已调度的不影响
PreferNoSchedule 表示尽量不调度
NoExecute表示不允许调度，已经运行的Pod副本会执行删除出的动作

kubectl run —image=nginx —image-pull-policy=Never test —replicas=4

  1. [liwm@rmaster01 liwm]$ kubectl run --image=nginx --image-pull-policy=Never test  --replicas=4 
  2. kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
  3. deployment.apps/test created
  4. [liwm@rmaster01 liwm]$ kubectl get pod -o wide 
  5. NAME                   READY   STATUS    RESTARTS   AGE   IP            NODE     NOMINATED NODE   READINESS GATES
  6. test-695b98cb4-5nf86   1/1     Running   0          7s    10.42.4.201   node01   <none>           <none>
  7. test-695b98cb4-fnwtc   1/1     Running   0          7s    10.42.2.253   node02   <none>           <none>
  8. test-695b98cb4-gm4zf   1/1     Running   0          7s    10.42.4.200   node01   <none>           <none>
  9. test-695b98cb4-svghx   1/1     Running   0          7s    10.42.2.252   node02   <none>           <none>
  10. [liwm@rmaster01 liwm]$ kubectl taint node node01 app=test:NoSchedule 
  11. node/node01 tainted
  12. [liwm@rmaster01 liwm]$ kubectl run --image=nginx --image-pull-policy=Never test1  --replicas=4 
  13. kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
  14. deployment.apps/test1 created
  15. [liwm@rmaster01 liwm]$ kubectl get pod -o wide 
  16. NAME                     READY   STATUS    RESTARTS   AGE   IP            NODE     NOMINATED NODE   READINESS GATES
  17. test-695b98cb4-5nf86     1/1     Running   0          67s   10.42.4.201   node01   <none>           <none>
  18. test-695b98cb4-fnwtc     1/1     Running   0          67s   10.42.2.253   node02   <none>           <none>
  19. test-695b98cb4-gm4zf     1/1     Running   0          67s   10.42.4.200   node01   <none>           <none>
  20. test-695b98cb4-svghx     1/1     Running   0          67s   10.42.2.252   node02   <none>           <none>
  21. test1-7b5b76c466-2hfdk   1/1     Running   0          10s   10.42.2.3     node02   <none>           <none>
  22. test1-7b5b76c466-2pnfk   1/1     Running   0          10s   10.42.2.2     node02   <none>           <none>
  23. test1-7b5b76c466-cmxgd   1/1     Running   0          10s   10.42.2.4     node02   <none>           <none>
  24. test1-7b5b76c466-q44dp   1/1     Running   0          10s   10.42.2.254   node02   <none>           <none>
  25. [liwm@rmaster01 liwm]$

NoExecute 迁移pod

  1. [liwm@rmaster01 liwm]$ kubectl run --image=nginx --image-pull-policy=Never  test --replicas=4 
  2. kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
  3. deployment.apps/test created
  4. [liwm@rmaster01 liwm]$ kubectl get pod -o wide 
  5. NAME                   READY   STATUS    RESTARTS   AGE   IP            NODE     NOMINATED NODE   READINESS GATES
  6. test-695b98cb4-6f7g8   1/1     Running   0          5s    10.42.4.202   node01   <none>           <none>
  7. test-695b98cb4-bv8d8   1/1     Running   0          5s    10.42.2.6     node02   <none>           <none>
  8. test-695b98cb4-q5kkh   1/1     Running   0          5s    10.42.2.5     node02   <none>           <none>
  9. test-695b98cb4-s2qr2   1/1     Running   0          5s    10.42.4.203   node01   <none>           <none>
  10. [liwm@rmaster01 liwm]$ kubectl taint node node01 app=test:NoExecute
  11. node/node01 tainted
  12. [liwm@rmaster01 liwm]$ kubectl get pod -o wide 
  13. NAME                   READY   STATUS        RESTARTS   AGE   IP          NODE     NOMINATED NODE   READINESS GATES
  14. test-695b98cb4-bv8d8   1/1     Running       0          74s   10.42.2.6   node02   <none>           <none>
  15. test-695b98cb4-h552m   1/1     Running       0          7s    10.42.2.7   node02   <none>           <none>
  16. test-695b98cb4-k7gp5   1/1     Running       0          6s    10.42.2.8   node02   <none>           <none>
  17. test-695b98cb4-q5kkh   1/1     Running       0          74s   10.42.2.5   node02   <none>           <none>
  18. test-695b98cb4-s2qr2   0/1     Terminating   0          74s   <none>      node01   <none>           <none>
  19. [liwm@rmaster01 liwm]$ kubectl get pod -o wide 
  20. NAME                   READY   STATUS    RESTARTS   AGE   IP          NODE     NOMINATED NODE   READINESS GATES
  21. test-695b98cb4-bv8d8   1/1     Running   0          79s   10.42.2.6   node02   <none>           <none>
  22. test-695b98cb4-h552m   1/1     Running   0          12s   10.42.2.7   node02   <none>           <none>
  23. test-695b98cb4-k7gp5   1/1     Running   0          11s   10.42.2.8   node02   <none>           <none>
  24. test-695b98cb4-q5kkh   1/1     Running   0          79s   10.42.2.5   node02   <none>           <none>
  25. [liwm@rmaster01 liwm]$

宽容

Tolerations operator可以定义为：
Equal表示key是否等于value
Exists表示key是否存在，使用Exists无需定义vaule。

image.png image.png

master节点运行应用副本

  1. cat << EOF > taint.yaml
  2. apiVersion: apps/v1
  3. kind: DaemonSet
  4. metadata:
  5.   name: fluentd-elasticsearch
  6.   labels:
  7.     k8s-app: fluentd-logging
  8. spec:
  9.   selector:
  10.     matchLabels:
  11.       name: fluentd-elasticsearch
  12.   template:
  13.     metadata:
  14.       labels:
  15.         name: fluentd-elasticsearch
  16.     spec:
  17.       tolerations: #宽容
  18.       - key: node-role.kubernetes.io/master
  19.         operator: "Exists"
  20.         effect: NoSchedule
  21.       containers:
  22.       - name: fluentd-elasticsearch
  23.         image: nginx
  24.         imagePullPolicy: IfNotPresent
  25. EOF
  1. apiVersion: apps/v1
  2. kind: DaemonSet
  3. metadata:
  4.   name: fluentd-elasticsearch
  5.   labels:
  6.     k8s-app: fluentd-logging
  7. spec:
  8.   selector:
  9.     matchLabels:
  10.       name: fluentd-elasticsearch
  11.   template:
  12.     metadata:
  13.       labels:
  14.         name: fluentd-elasticsearch
  15.     spec:
  16.       tolerations: #宽容
  17.       - key: node-role.kubernetes.io/node
  18.         operator: "Exists" 
  19.         effect: NoSchedule
  20.       - key: node-role.kubernetes.io/etcd 
  21.         operator: "Exists"
  22.         effect: NoExecute
  23.       - key: node-role.kubernetes.io/controlplane
  24.         operator: "Exists"
  25.         effect: NoSchedule
  26.       containers:
  27.       - name: fluentd-elasticsearch
  28.         image: nginx
  29.         imagePullPolicy: IfNotPresent

给node设置污点
kubectl taint node node01 ssd=:NoSchedule
kubectl taint node node02 app=nginx-1.9.0:NoSchedule
kubectl taint node node02 test=test:NoSchedule

创建pod+tolerations

  1. cat << EOF > tolerations-pod.yaml
  2. apiVersion: v1
  3. kind: Pod
  4. metadata:
  5.   name: test1
  6. spec:
  7.   tolerations:
  8.   - key: "ssd"
  9.     operator: "Exists" #是否存在
  10.     effect: "NoSchedule"
  11.   containers:
  12.   - name: demo
  13.     image: polinux/stress
  14.     imagePullPolicy: IfNotPresent
  15.     command: ["stress"]
  16.     args: ["--vm", "1", "--vm-bytes", "150M", "--vm-hang", "1"]
  17. ---
  18. apiVersion: v1
  19. kind: Pod
  20. metadata:
  21.   name: test2
  22. spec:
  23.   tolerations:
  24.   - key: "app"
  25.     operator: "Equal" #等于
  26.     value: "nginx-1.9.0"
  27.     effect: "NoSchedule"
  28.   - key: "test"
  29.     operator: "Equal"
  30.     value: "test"
  31.     effect: "NoSchedule"
  32.   containers:
  33.   - name: demo
  34.     image: polinux/stress
  35.     imagePullPolicy: IfNotPresent
  36.     command: ["stress"]
  37.     args: ["--vm", "1", "--vm-bytes", "150M", "--vm-hang", "1"]
  38. EOF

image.png

  1. [root@master ~]# kubectl create deployment myapp --image=nginx 
  2. deployment.apps/myapp created
  3. [root@master ~]# 
  4. [root@master ~]# kubectl get pod 
  5. NAME                     READY   STATUS    RESTARTS   AGE
  6. myapp-687598b8b4-jlcbr   0/1     Pending   0          6s
  7. [root@master ~]# kubectl scale deployment myapp --replicas=3
  8. deployment.apps/myapp scaled
  9. [root@master ~]# kubectl get pod 
  10. NAME                     READY   STATUS    RESTARTS   AGE
  11. myapp-687598b8b4-8fvjp   0/1     Pending   0          5s
  12. myapp-687598b8b4-jlcbr   0/1     Pending   0          29s
  13. myapp-687598b8b4-t8vpb   0/1     Pending   0          5s
  14. [root@master ~]#