[VMC on AWS] Incorrect External TGW routes showing up in SDDC group routing table

Products

• VMware Cloud on AWS

Issue/Introduction

Provide steps to clear the stale routes so the SDDC Group shows the correct routes on the External TGW.

Symptoms:
Routes were added/removed on an External TGW (Customer Managed TGW) and they are not showing under the Route Table for the SDDC Group. Stale routes are being seen from the previous static routes on the External TGW, and the newly added routes may not be showing up in the SDDC Group.

All routes are showing correct in the AWS Console for the External TGW, but the VMC SDDC Group is showing incorrect routes.

Cause

This is caused by the External TGW being in a Connecting/Pending state when the routes are added/removed.

Resolution

• Ensure the External TGW and SDDC Group are showing as Connected, and not Connected/Pending when adding/removing routes.
   
• Additionally, ensure the correct static routes are showing under the External TGW tab in the SDDC Group (Path: SDDC Group - External TGW - Expand out the Arrow for the correct External TGW - Pencil Icon - Static Routes).

If the above are both validated, please proceed with filing a Support Request with VMC Global Support Creating and managing Broadcom support cases

When creating an SR, please provide the below information:

• SDDC ID and SDDC Group name
• Screenshot of the routes showing under the External TGW on the AWS Console
• Confirmation on what the "Incorrect" routes are and the "Correct" routes are in the SDDC Group

Additional Information

Impact/Risks:
This will cause stale routes to show on the SDDC Group Route table.