Does using Managed Identity as compared to Connection String(With SAS key) to post events to event Hub from Azure Function have any impact when concurrent executions of the Azure functions increase?

Question

We have an Azure Function(Premium V2 consumption plan) that posts events to event hub. Right now, for connecting to event hub, the connection string is used with SAS token. We were looking for a better or a more secure way to do this connection and came up with using Managed Identity. The question is: What happens when the concurrent executions of the Azure Function increases(Scaling). Earlier because we were using connection string, there was no dependency involved. Now, if we go ahead with Managed identity, we're introducing a dependency of Managed Identity service to do its magic. Will the service that provides a token for Managed Identity scale when the azure function scales?

Answer 1

Managed Identity is like fetching a token from Azure AD except that you don't have to manage the environment variables normally needed for a client credentials flow. Also, since the SDK using with Functions already handles token caching and refreshing, it should scale with ease alongside your function app.