Azure Functions Deployment Slot and User-Assigned Managed Identities

Question

Hi everyone,

I’m working with an HTTP-triggered Azure Function that uses environment variables and a User-Assigned Managed Identity (UMI). I’ve also set up a deployment slot for this function.

I noticed that while environment variables are carried over to the deployment slot, the User-Assigned Managed Identity is not automatically assigned to the slot. Is this the expected behavior?

If so, is there any official documentation that outlines what configurations (like managed identities) need to be manually set up when creating a deployment slot?
Do they need to be setup each time the function is pushed to the slot?

Thanks in advance!

Answer 1

Hi Jean David Ruvini,

Welcome to the Microsoft Q&A Platform! Thank you for asking your question here.

Yes, this is the expected behavior. Deployment slots in Azure Functions do not automatically inherit User-Assigned Managed Identities (UMI) or System-Assigned Managed Identities. Managed Identities must be explicitly assigned to each deployment slot because these identities are associated with the slot's unique underlying resources rather than the application itself.

Please refer to the below document on the same

Managed Identities in Azure Functions

Regarding your second question, you do not need to set up the UMI each time you push the function to the slot. Once you have assigned the UMI to the deployment slot, it will be available for use in all deployments to that slot.

If this answers your query, do click Accept Answer and Yes for was this answer helpful. And, if you have any further query do let us know.