Our company (WISP company) has a management computer located on one gateway (Gateway A) with multiple routers with redundant routes to a second gateway (Gateway B). The traffic going through Gateway B is not visible through Gateway A when Gateway B is the active route. I'm needing the server to be able to see clients dynamically whether it's going through either gateway. Both Gateway A and Gateway B are controlled by Edge Routers.
EDIT
By gateway I mean a path to the internet. We are running a public webpage on the server as well!