Tolerations for Scheduling SE Pod on OpenShift Node

Overview

Taints on a node prohibit scheduling of pods in an OpenShift deployment. Tolerations are applied to pods for scheduling onto nodes with matching taints. In OpenShift integration with Avi Vantage, taints and tolerations are used for scheduling Service Engines onto tainted nodes.

For more information on taints and tolerations, refer to Taints and Tolerations.

If a node is tainted with an effect No Schedule, an SE pod can not be scheduled on the node. Starting with Avi Vantage release 17.2.14, toleration is added as a part of the OpenShift cloud configuration to schedule SE pod even on the tainted node.

Configuring Avi Vantage for Tolerations

Toleration for a node in the OpenShift cloud is configured using the se_pod_tolerations sub-mode under the oshiftk8s_configuration mode. SE pod is scheduled on a node if the node matches with the tolerations attributes. Log in to the shell access for the Avi Controller and execute the following commands.


 [admin:10.10.10.1]: > cloud_configuration
 [admin:10.10.10.1]: cloud> oshiftk8s_configuration
 [admin:10.10.10.1]: cloud:oshiftk8s_configuration> se_pod_tolerations
 New object being created
 [admin:10-10.10.1]: cloud:oshiftk8s_configuration:se_pod_tolerations> key k1
 [admin:10.10.10.1]: cloud:oshiftk8s_configuration:se_pod_tolerations> value v1
 [admin:10.10.10.1]: cloud:oshiftk8s_configuration:se_pod_tolerations> effect
 no_execute           Effect NoExecute to match
 no_schedule          Effect NoSchedule to match
 prefer_no_schedule   Effect PreferNoSchedule to match
 [admin:10.10.10.1]: cloud:oshiftk8s_configuration:se_pod_tolerations> effect no_schedule
 [admin:10.10.10.1]: cloud:oshiftk8s_configuration:se_pod_tolerations> operator equal
 [admin:10.10.10.1]: cloud:oshiftk8s_configuration:se_pod_tolerations> save
 

Additional Information

For more information on OpenShift deployment with Avi Vantage, refer to Installing Avi Vantage in OpenShift/Kubernetes.