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@@ -4,9 +4,6 @@ assignees:
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- kevin-wangzefeng
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- bsalamat
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title: Assigning Pods to Nodes
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redirect_from:
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- "/docs/user-guide/node-selection/"
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- "/docs/user-guide/node-selection/index.html"
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---
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You can constrain a [pod](/docs/concepts/workloads/pods/pod/) to only be able to run on particular [nodes](/docs/concepts/nodes/node/) or to prefer to
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@@ -205,7 +202,7 @@ If omitted, it defaults to the namespace of the pod where the affinity/anti-affi
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If defined but empty, it means "all namespaces."
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All `matchExpressions` associated with `requiredDuringSchedulingIgnoredDuringExecution` affinity and anti-affinity
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must be satisfied for the pod to schedule onto a node.
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must be satisfied for the pod to schedule onto a node.
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For more information on inter-pod affinity/anti-affinity, see the design doc
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[here](https://git.k8s.io/community/contributors/design-proposals/podaffinity.md).
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@@ -236,7 +233,7 @@ taint created by the `kubectl taint` line above, and thus a pod with either tole
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to schedule onto `node1`:
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```yaml
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tolerations:
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tolerations:
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- key: "key"
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operator: "Equal"
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value: "value"
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@@ -244,7 +241,7 @@ tolerations:
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```
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```yaml
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tolerations:
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tolerations:
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- key: "key"
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operator: "Exists"
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effect: "NoSchedule"
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@@ -304,7 +301,7 @@ kubectl taint nodes node1 key2=value2:NoSchedule
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And a pod has two tolerations:
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```yaml
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tolerations:
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tolerations:
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- key: "key1"
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operator: "Equal"
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value: "value1"
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@@ -327,7 +324,7 @@ an optional `tolerationSeconds` field that dictates how long the pod will stay b
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to the node after the taint is added. For example,
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```yaml
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tolerations:
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tolerations:
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- key: "key1"
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operator: "Equal"
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value: "value1"
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@@ -345,7 +342,7 @@ Taints and tolerations are a flexible way to steer pods away from nodes or evict
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pods that shouldn't be running. A few of the use cases are
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* **dedicated nodes**: If you want to dedicate a set of nodes for exclusive use by
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a particular set of users, you can add a taint to those nodes (say,
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a particular set of users, you can add a taint to those nodes (say,
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`kubectl taint nodes nodename dedicated=groupName:NoSchedule`) and then add a corresponding
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toleration to their pods (this would be done most easily by writing a custom
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[admission controller](/docs/admin/admission-controllers/)).
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@@ -410,7 +407,7 @@ that the partition will recover and thus the pod eviction can be avoided.
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The toleration the pod would use in that case would look like
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```yaml
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tolerations:
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tolerations:
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- key: "node.alpha.kubernetes.io/unreachable"
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operator: "Exists"
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effect: "NoExecute"
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Andrew Chen