Migrating Azure Basic Load Balancers to Standard Load Balancers in TPCF

Products

• VMware Tanzu Application Service
• VMware Tanzu Platform - Cloud Foundry

Issue/Introduction

Microsoft has announced that Azure Basic Load Balancers (BLBs) will reach End-of-Life (EOL) by the end of September 2025. As a result, customers using TPCF (Tanzu Platform for Cloud Foundry) will need to transition from Basic Load Balancers to Standard Load Balancers (SLBs) to maintain support and avoid service disruptions.

Resolution

You'll note that there is a linked instructions for the azure cpi regarding a lb migration describe a similar serial migration process: https://github.com/cloudfoundry/bosh-azure-cpi-release/tree/master/docs/advanced/migrate-basic-lb-to-standard-lb. 

We believe the migration would roughly look like the following: 

1) Manually create new standard LBs and associated IPs for the desired job (e.g., Diego Brain). One should note that this would be a NEW Public IP, so if they wish to avoid downtime, they would need some manually configured routing during the cutover (the previous linked document describes doing this with HAProxy). 
2) Update the load balancer for that job with the name of the new load balancer on the Resource Config tab for TPCF and deploy. 

We strongly recommend that the customer test this scenario using a lab environment that reflects their unique configuration to ensure that behavior is as expected for the migration. We cannot account for all potential custom configuration that the customer might have, so the safest way forward is to test this change with a non-critical environment.