污点状态：
-
NoSchedule：如果 Node 上带有污点 effect 为 NoSchedule，而 Node 上不带相应容忍，Kubernetes 就不会调度 Pod 到这台 Node 上。
-
PreferNoShedule：如果 Node 上带有污点 effect 为 PreferNoShedule，这时候 Kubernetes 会努力不要调度这个 Pod 到这个 Node 上。
-
NoExecute：如果 Node 上带有污点 effect 为 NoExecute，这个已经在 Node 上运行的 Pod 会从 Node 上驱逐掉。没有运行在 Node 的 Pod 不能被调度到这个 Node 上。
污点值：
- 污点 value 的值可以为 NoSchedule、PreferNoSchedule 或 NoExecute
污点属性：
-
污点是k8s集群的pod中的一种属性
-
污点属性分为以上三种
污点组成：
- key、value 及一个 effect 三个元素
<key>=<value>:<effect>1、设置单污点及单容忍度
- kubectl taint nodes master1 node-role.kubernetes.io/master=:NoSchedule
-
- kubectl taint node node1 key1=value1:NoSchedule # 设置value值
-
- kubectl taint node master1 key2=:PreferNoSchedule # 不设置value值
2、设置多污点及多容忍度
- kubectl taint nodes node1 key1=value1:NoSchedule
-
- kubectl taint nodes node1 key1=value1:NoExecute
-
- kubectl taint nodes node1 key2=value2:NoSchedule
3、查看pod中的污点状态
- [root@master1 ~]# kubectl describe nodes master1
- Name: master1
- Roles: master
- Labels: beta.kubernetes.io/arch=amd64
- beta.kubernetes.io/os=linux
- kubernetes.io/arch=amd64
- kubernetes.io/hostname=master1
- kubernetes.io/os=linux
- node-role.kubernetes.io/master=
- Annotations: flannel.alpha.coreos.com/backend-data: {"VNI":1,"VtepMAC":"36:51:e1:31:e5:9e"}
- flannel.alpha.coreos.com/backend-type: vxlan
- flannel.alpha.coreos.com/kube-subnet-manager: true
- flannel.alpha.coreos.com/public-ip: 192.168.200.3
- kubeadm.alpha.kubernetes.io/cri-socket: /var/run/dockershim.sock
- node.alpha.kubernetes.io/ttl: 0
- volumes.kubernetes.io/controller-managed-attach-detach: true
- CreationTimestamp: Wed, 13 Jan 2021 06:04:10 -0500
- Taints: node-role.kubernetes.io/master:NoSchedule # 污点状态及容忍度
- Unschedulable: false
- Lease:
- HolderIdentity: master1
- AcquireTime: <unset>
- RenewTime: Thu, 14 Jan 2021 01:14:07 -0500
- Conditions:
- Type Status LastHeartbeatTime LastTransitionTime Reason Message
- ---- ------ ----------------- ------------------ ------ -------
- NetworkUnavailable False Wed, 13 Jan 2021 06:12:43 -0500 Wed, 13 Jan 2021 06:12:43 -0500 FlannelIsUp Flannel is running on this node
- MemoryPressure False Thu, 14 Jan 2021 01:11:17 -0500 Wed, 13 Jan 2021 06:50:32 -0500 KubeletHasSufficientMemory kubelet has sufficient memory available
- DiskPressure False Thu, 14 Jan 2021 01:11:17 -0500 Wed, 13 Jan 2021 06:50:32 -0500 KubeletHasNoDiskPressure kubelet has no disk pressure
- PIDPressure False Thu, 14 Jan 2021 01:11:17 -0500 Wed, 13 Jan 2021 06:50:32 -0500 KubeletHasSufficientPID kubelet has sufficient PID available
- Ready True Thu, 14 Jan 2021 01:11:17 -0500 Wed, 13 Jan 2021 06:50:32 -0500 KubeletReady kubelet is posting ready status
- Addresses:
- InternalIP: 192.168.200.3
- Hostname: master1
- Capacity:
- cpu: 4
- ephemeral-storage: 17394Mi
- hugepages-1Gi: 0
- hugepages-2Mi: 0
- memory: 2897500Ki
- pods: 110
- Allocatable:
- cpu: 4
- ephemeral-storage: 16415037823
- hugepages-1Gi: 0
- hugepages-2Mi: 0
- memory: 2795100Ki
- pods: 110
- System Info:
- Machine ID: feb4edfea2404d3c8ad028ca4593bb32
- System UUID: C6F44D56-0F24-6114-23E7-8DF6CD4E4CFE
- Boot ID: afcc0ef6-d767-4b97-9a7b-9b2500757f2e
- Kernel Version: 3.10.0-862.el7.x86_64
- OS Image: CentOS Linux 7 (Core)
- Operating System: linux
- Architecture: amd64
- Container Runtime Version: docker://19.3.0
- Kubelet Version: v1.18.2
- Kube-Proxy Version: v1.18.2
- PodCIDR: 10.244.0.0/24
- PodCIDRs: 10.244.0.0/24
- Non-terminated Pods: (6 in total)
- Namespace Name CPU Requests CPU Limits Memory Requests Memory Limits AGE
- --------- ---- ------------ ---------- --------------- ------------- ---
- kube-system etcd-master1 0 (0%) 0 (0%) 0 (0%) 0 (0%) 19h
- kube-system kube-apiserver-master1 250m (6%) 0 (0%) 0 (0%) 0 (0%) 19h
- kube-system kube-controller-manager-master1 200m (5%) 0 (0%) 0 (0%) 0 (0%) 19h
- kube-system kube-flannel-ds-wzf7w 100m (2%) 100m (2%) 50Mi (1%) 50Mi (1%) 19h
- kube-system kube-proxy-7h5sb 0 (0%) 0 (0%) 0 (0%) 0 (0%) 19h
- kube-system kube-scheduler-master1 100m (2%) 0 (0%) 0 (0%) 0 (0%) 19h
- Allocated resources:
- (Total limits may be over 100 percent, i.e., overcommitted.)
- Resource Requests Limits
- -------- -------- ------
- cpu 650m (16%) 100m (2%)
- memory 50Mi (1%) 50Mi (1%)
- ephemeral-storage 0 (0%) 0 (0%)
- hugepages-1Gi 0 (0%) 0 (0%)
- hugepages-2Mi 0 (0%) 0 (0%)
- Events: <none>
4、过滤出有几台节点存在污和容忍度是什么
- [root@master1 ~]# kubectl describe node master1 | grep Taints
- Taints: node-role.kubernetes.io/master:NoSchedule
-
- [root@master1 ~]# kubectl describe node master2 | grep Taints
- Taints: node-role.kubernetes.io/master:NoSchedule
-
- [root@master1 ~]# kubectl describe node master3 | grep Taints
- Taints: node-role.kubernetes.io/master:NoSchedule
5、有无污点返回的结果
- Taints: node-role.kubernetes.io/master:NoSchedule # 有污点
-
- Taints: <none> # 没污点
6、删除污点使其pod能够调度和使用
- kubectl taint node master1 node-role.kubernetes.io/master:NoSchedule-
-
- kubectl taint nodes master1 key:NoSchedule-
