SDWAN Hub rebalance in a cluster causes incorrect routing

Products

• VMware Aria Suite

Issue/Introduction

Symptoms:

In a cluster topology in an SD-WAN environment, after an activity that would cause edges to change cluster member, incorrect routing might be seen, causing:

• Traffic to specific subnets being dropped
• Performance degradation or "slowness" on affected traffic

This may occur after any of the following:

• A "Rebalance Hub Cluster" was triggered on a cluster member
• Upgrade or reboot of a spoke
• Upgrade or reboot of a HUB

 

Environment

VMware SD-WAN

Cause

This is a known issue affecting SD-WAN Gateways, and is tracked under ID: 90884 

After a HUB rebalance, route preference is not properly updated on the VCG before providing the routes to the edges. Causing for the incorrect order to be used for routing.

 

Resolution

Upgrade the SD-WAN Gateways used by the edges to a fixed releases:
Release 5.1.0.0 (R5100-20221204-GA ) or later

For information on how to upgrade please check the following article: VMware SD-WAN Software Upgrade FAQs

Workaround:
To work around this issue, contact VMware Support and note this Article ID (91022) in the problem description. For more information, see VMware SD-WAN – Support

Additional Information

Impact/Risks:
The workaround applied by technical support will cause a brief disruption for the affected subnet briefly on all devices.
General routing through a SD-WAN Gateway might be affected while being upgraded.