Understanding VNet-to-VNet

A VNet-to-VNet connection is a simple way to connect multiple VNets together. Connecting a virtual network to another virtual network is similar to creating a site-to-site IPSec connection to an on-premises environment. Both connection types use the Azure virtual private network (VPN) gateway. This VPN gateway provides a secure IPSec/IKE tunnel, and each side of the connection communicates in the same way. The only difference is in the way the local network gateway is configured.

The local network gateway address space is automatically created and populated when a VNet-to-VNet connection is created. When the address space of one VNet has been updated, this results in the other VNet automatically routing its traffic to the updated address space. This makes it more efficient and quicker to create a VNet-to-VNet connection instead of a Site-to-Site (S2S) connection.

There are a couple of reasons why you might want to set up a VNet-to-VNet connection, as...