# Edge to edge routing

* For example, if VPC A and VPC B are peered, and VPC A has any of these connections, then instances in VPC B cannot use the connection to access resources on the other side of the connection.<br>
* Similarly, resources on the other side of a connection cannot use the connection to access VPC B.

![](https://1720417355-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MPZQSmHKLs82TRAPZ78%2F-MPe-_StZPnXTZianDym%2F-MPeqhyqEYEW5lZ9NpvK%2Fimage.png?alt=media\&token=8b6fb5fd-3c40-4377-8f4f-bc99d1243794)

* To **increase the fault tolerance** in this case, you can:
  * Establish a **hardware VPN over the Internet between the VPC and the on-premises network**.
  * Establish **another AWS Direct Connect connection and private virtual interface in the same AWS region**.&#x20;