We have set up a ANF in a delegated subnet and can access it from other servers in the Vnet but cannot figure out how to access it from our servers on-premises via out Express Route link and the Express Route Gateway in the hub. According to the documentation the ANF subnet learns return route information from the gateway but we can’t figure out how or if that is happening.
Has anyone managed to get this working? I would be grateful for any information to help us get this working.
For route learning to function, you must enable Border Gateway Protocol route propagation when creating the GatewaySubnet; which is the step taken before you created the ExpressRoute Gateway. BGP is what's responsible for advertising the on-premises routes.