Unable to save Avi virtual service configuration with error: ""Virtual service can only use ACTIVE_STANDBY_SE_2 Tag if Service Engine Group is configured for Legacy Active Standby HA and load distribution is enabled"

Products

• VMware Avi Load Balancer

Issue/Introduction

When editing and attempting to save a Virtual Service configuration, the operation fails with the following error message:

Virtual service can only use ACTIVE_STANDBY_SE_2 Tag if Service Engine Group is configured for Legacy Active Standby HA and load distribution is enabled.

 This error indicates a configuration mismatch between the Virtual Service's tag settings and the Service Engine Group configuration.

Screenshot of the error from Avi UI:

Cause

This issue is caused by a configuration inconsistency that is created when a Service Engine Group's settings are modified after Virtual Services have been deployed to it.

The sequence of events is as follows:

1. A Service Engine Group is initially configured for Legacy Active/Standby HA with the Distribute Load option enabled.
2. When Virtual Services are created in this group, the Avi Controller automatically assigns the active_standby_se_2 tag to some of them as part of its placement and load distribution logic.
3. At a later time, an administrator disables the Distribute Load option on the Service Engine Group.
4. This change in the Service Engine Group does not automatically change the now-invalid active_standby_se_2 tag from the existing Virtual Services.

The Virtual Service is therefore left with a stale configuration tag that conflicts with the current state of the Service Engine Group. This conflict triggers the validation error when a user attempts to edit and save the Virtual Service.

 

Resolution

To resolve this configuration conflict, you must manually update the tag to active_standby_se_1 on each affected Virtual Service. This is a non-disruptive change performed via the Avi Controller command-line interface (CLI).

To correct the invalid HA tag, log in to the Avi Controller CLI and execute the following commands for each affected Virtual Service, replacing <vs-name> with the specific service name:

> configure virtualservice <vs-name>
> active_standby_se_tag active_standby_se_1
> save

Repeat these steps for any additional Virtual Services exhibiting the same error. After this change, you will be able to edit and save the Virtual Service through the UI without encountering the validation error.

Additional Information

Reference KB for service engine group configuration options which include more details about the 'Enable load distribution' feature:  https://techdocs.broadcom.com/us/en/vmware-security-load-balancing/avi-load-balancer/avi-load-balancer/30-2/load-balancing-overview/service-engine-group/create-se-group/placement-tab.html