I'm working on migrating an application to a client's Azure cloud setup. We've been able to freely create VNETs and subnets in our own cloud subscription, but now that we're using the client's resources, we're running into some subnet delegation challenges. Microsoft suggests a minimum subnet size for their delegations, but given that my internal application doesn't require extensive scaling—only a few hundred users daily—I'm worried about the provided /24 VNET size. The container environment we're planning to use has a minimum requirement of /23. My concern is whether it's feasible to use a smaller subnet than what Microsoft specifies. If I do, could that lead to issues down the line, especially considering the container app has a max replica of 2?
2 Answers
I'm pretty sure if you go with a subnet smaller than /23, your deployment will fail. You'll likely get an error saying something like 'subnet size too small - must be /23 or larger.' It's a strict requirement for those delegations.
You might want to avoid using the Consumption Only environment. It’s been deprecated. Instead, try using the Workload Profiles environment, which allows for a smaller VNET integration of /27. The /23 requirement is mostly for older environment types!
But keep in mind, the dedicated plans will have a charge of $0.1 per hour for the plan alongside private endpoints, which can rack up to at least $140 a month even if you’re barely using it.
Just to clarify, going with a Consumption Only type doesn’t offer any real benefits—only drawbacks. It’s best to skip it entirely.