6.3. Assigning machine set resources to infrastructure nodes

Procedure

1. Use the following command to add a taint to the infra node to prevent scheduling user workloads on it:

   $ oc adm taint nodes <node_name> <key>:<effect>

   For example:

   $ oc adm taint nodes node1 node-role.kubernetes.io/infra:NoSchedule

   This example places a taint on node1 that has key node-role.kubernetes.io/infra and taint effect NoSchedule. Nodes with the NoSchedule effect schedule only pods that tolerate the taint, but allow existing pods to remain scheduled on the node.

   注意

   If a descheduler is used, pods violating node taints could be evicted from the cluster.

2. Add tolerations for the pod configurations you want to schedule on the infra node, like router, registry, and monitoring workloads. Add the following code to the Pod object specification:

   tolerations:
     - effect: NoSchedule 1
       key: node-role.kubernetes.io/infra 2
       operator: Exists 3

   1

   Specify the effect that you added to the node.

   2

   Specify the key that you added to the node.

   3

   Specify the Exists Operator to require a taint with the key node-role.kubernetes.io/infra to be present on the node.

   This toleration matches the taint created by the oc adm taint command. A pod with this toleration can be scheduled onto the infra node.

   注意

   Moving pods for an Operator installed via OLM to an infra node is not always possible. The capability to move Operator pods depends on the configuration of each Operator.

3. Schedule the pod to the infra node using a scheduler. See the documentation for Controlling pod placement onto nodes for details.