We have HQ site and DR connected via DS3 as shown in the frawing
There are three VLANs bridged across the link, one of the VLANs has a 16 bit subnet mask.
Recently we had a problem with one of the hosts in HQ (10.1.11.1/16, after being replaced) was taking a different path to get to a remote host (shown as hanging off of MPLS cloud).
Normally, the host in HQ would go default gateway 10.1.1.1 and the next hop would be the ethernet interface of the local router in vlan 7 (10.7.7.254), then to MPLS cloud, then to remote host.
What was happening was the host went to the default gateway, but the next hop was the ethernet interface of the remote router in DR, vlan 8 (10.8.8.254), then to MPLS cloud, then to remote host.
At first I thought the default gateway had been incorrectly configured with the BVI in that site, but what it turned out to be was the subnet mask on host 10.1.11.1 was only 8 bits.
Once the mask was changed to 16 bit, the route path was correct.
What was causing the DR BVI to be more desirable as a next hop with an 8 bit mask?