We're remediating a legacy Azure environment that currently has roughly 300 resources in a single subscription, most of them created through the portal. We've deployed the Azure Landing Zones accelerator and built a Terraform-based subscription vending process, but the migration is blocked by the subscription limit.
We expect to need around 50–60 subscriptions so workloads can be separated properly, with dedicated production and staging environments. Support raised our limit from 5 to 10, but they're asking for a more specific business justification before approving a larger increase. I've already explained that the request is part of an Azure Landing Zones and infrastructure-as-code migration.
What information or escalation path has worked for getting a substantially higher subscription limit approved?
1 Answer
Support will usually want a concrete capacity plan rather than just a reference to best practices. Put together a short document listing the target subscription count, the management-group structure, which workloads will go into each subscription, expected growth, environments, billing ownership, and the controls you’ll apply with Terraform and Azure Policy. Explain why keeping everything in one subscription creates operational, security, quota, and blast-radius problems. Include the fact that you already have an automated vending process and an estimated migration timeline. Ask support to escalate the request to the subscription limits or capacity team and attach that plan to the case.
That makes sense. We currently have the target layout and vending process documented, but I focused more on the architecture than on projected growth and the operational risks of staying in one subscription. I’ll turn it into a formal capacity and migration plan for the case.