I have an ExpressRoute circuit configured with a connection to a Version 2 (Resource Manager) Azure Virtual Network. I also have an additional Virtual Network in a different Subscription which I need to connect to the same circuit.
The instructions on connecting another Virtual Network in a different Subscription are a little confusing. It’s also worth noting that some of the parameters are different now with the latest version of the PowerShell Azure cmdlets. The original instructions may be found at this URL: https://azure.microsoft.com/en-us/documentation/articles/expressroute-howto-linkvnet-arm/#connect-a-virtual-network-in-a-different-azure-subscription-to-an-expressroute-circuit