Prepend the private ASN on the BGP announcements to AWS from the second data center. Add a second VIF in the first Direct Connect connection. Advertise the same network without any prepends from the first data center. Implement the same setup for the BGP announcement from AWS to the two data centers.

Tag the BGP announcements with the local preference BGP community tags. Set the tag to high preference for the first data center. Set the tag to low preference for the second data center. Configure the second data center’s router to have a lower local preference for the direct AWS BGP advertisements than for the advertisement from the fist data center.

Configure the Direct Connect gateway to prefer routing through the Direct Connect connection with the first data center. Configure the second data center’s router to have a lower local preference for the direct AWS BGP advertisements than for the advertisement from the first data center.

Configure the focal AWS Region BGP community tag on the BGP route that is advertised from the fist data center. Configure AS_PATH prepends on the BGP announcements from the second data center.