There are two types of Azure Virtual Network peering: regional and global.
Regional virtual network peering connects Azure virtual networks that exist in the same region.
Global virtual network peering connects Azure virtual networks that exist in different regions.
You can create a global peering of virtual networks in any Azure public cloud region, or in any China cloud region.
Global peering of virtual networks in different Azure Government cloud regions isn’t permitted.
A virtual network can have only one VPN gateway.
Gateway transit is supported for both regional and global virtual network peering.
To create a peering, you need two virtual networks.
The second virtual network in the peering is referred to as the remote network.
Virtual network peering is nontransitive. The communication capabilities in a peering are available to only the virtual networks and resources in the peering. Other mechanisms have to be used to enable traffic to and from resources and networks outside the private peering network.
Suppose you have three virtual networks: A, B, and C. You establish virtual network peering between networks A and B, and also between networks B and C. You don’t set up peering between networks A and C. The virtual network peering capabilities that you set up between networks B and C don’t automatically enable peering communication capabilities between networks A and C.
