What effect does selecting an app service location in Azure have on a web app?

Question

I am creating a new web app in a new Azure account. I have set up a few resource groups for different geographical locations. When I am creating the web app, I select the appropriate resource group but it also wants me to specify a service plan for the app. I kinda get the difference between a resource group and service plan, but why is it forcing me to choose a geographical location for the service plan when I have already identified the one I want in the resource?

Am I right in thinking the web app will be physically located in the region selected for the resource? If so, what effect does selecting a different region for the service plan have?

Answer 1

A resource group is simply a naming/permissions/billing container. Like other Azure resources, you must choose a region for your resource group. However, this has zero to do with the region for the resources within the resource group.

An App Service Plan's region is where the web apps within that service plan will run. There are no rules that say it must be in the same region as the resource group (you can place either one in any region). Further: You do not need to colocate services within a resource group in the same region (though splitting them across region will have latency/bandwidth/cost implications).