问题
Can Site-to-Site Cross-Premises Connectivity technique explained in this document be used to connect two azure vms in different region, may be via an on-premises network?
回答1:
When building a Virtual Network in Azure, it is created within a specific data center. If you take a look at the Virtual Network creation page (as illustrated in the doc you referenced), you'll see that you need to select the datacenter to associate the vnet with:
You may then add any of your cloud services in that datacenter to that particular vnet. There's no mechanism to span the vnet across datacenters.
Per your question about routing through your on-premises datacenter: If you had two VPN devices, you can establish VPNs to two vnets in two datacenters. However: You'd need to figure out some type of routing scheme to bridge the two. Also: You'd be incurring latency both between DC1 -> on-prem, and on-prem -> DC2.
You'd be better off just connecting via public endpoints and placing IP restrictions on the endpoints to only allow inbound traffic from the cloud service on the opposing datacenter.
来源：https://stackoverflow.com/questions/20537842/connect-two-azure-vms-across-regions-via-vpn