Batch Restart Option for Avi Service Engines in OpenShift Cloud

Overview

For an Avi Service Engine (SE), the following are the few configuration parameters that can be changed:

  • CPU
  • Memory
  • Log disc size

For the resource changes to take effect, all the SEs restart in a Service Engine group. Due to this, traffic for all the virtual services associated with the SEs in the SE group is disrupted. Starting with Avi Vantage release 18.1.5, disruption of virtual service traffic can be avoided by using restart SEs in batches option in an OpenShift deployment.

Restarting Service Engines in Batches

The se_restart_batch_size configuration knob is used to initiate restart of SEs in batches. The default value of the batch size is 1.

Batch Size
The configuration changes are applied to the number of SEs equal to the batch size value provided in the se_restart_batch_size command.

Based on the batch size, SEs in an SE group is selected. SEs state changes to disabled mode and all the virtual services associated with the selected SEs are migrated to the active SEs in the SE group. All the configuration changes are applied to the SEs in the batch.

This mode of configuration change is non-disruptive.

Note: If the migration of virtual services is not successful or SEs state is error disabled mode, SEs retry for 5 times. If the migration is not successful after the maximum number of retries, the force restart command is executed.

Login to the Avi CLI, and use the shell mode to execute the configure Default-Cloud command. Select the se_restart_batch_size <batch value&gt configuration knob under the oshiftk8s_configuration sub mode as shown below.


admin@10-10-1-1:~$ shell
Login: admin
Password:

[admin:10-10-1-1]: > configure cloudproperties

[admin:10-10-1-1]: > configure cloud Default-Cloud
[admin:10-10-1-]: cloud> oshiftk8s_configuration
[admin:10-10-1-1]: cloud:oshiftk8s_configuration> se_restart_batch_size 2

If there is a requirement to avoid 5 retrials, use the force restart option, use the se_restart_force configuration knob as shown below.


admin@10-10-1-1:~$ shell
Login: admin
Password:

[admin:10-10-1-1]: > configure cloudproperties

[admin:10-10-1-1]: > configure cloud Default-Cloud
[admin:10-10-1-]: cloud> oshiftk8s_configuration
[admin:10-10-1-1]: cloud:oshiftk8s_configuration> se_restart_force