How to perform automatic failover between two sites.
We've got an interesting setup that is working fine for us, but has no failover currently so looking for suggestions.
At one of our sites, we have 150/150 fiber from our ISP. We also have a COLO rack at this ISP where we moved some of our servers (due to construction, never moved them back), and our Watchguard. As the ISP controls the fiber, they were able to setup a transparent bridge between our office and the colo. So basically there is a ethernet cable coming off our core switch at our site, it goes to their cisco box, then to a media converter, and into fiber.
So there is no routing needed for devices on either side to talk to eachother, it's totally transparent to users/devices.
At our site, we have a backup 50/10 DSL connection. This used to be setup for auto-failover before we moved the WG to the colo. While I could technically get this DSL connection hooked into that WG at the colo to act as a backup, it would only help in the event that the ISP's connection to the internet went down, but our fiber connection remained online. So not much good as a backup.
I'd like to get us setup so users will generally goto the WG at the colo, but if there is a problem, automatically switch over to another WG we'll setup at the actual site. I can manually do this now by either changing people's gateway, or by having an identical config on the 2nd box, and just keep it unplugged.
Does what I'm hoping to do make sense? Is this doable? If so, would the WG on site need to be the same model (M370)? or could we have a smaller T55 or similar?
Thanks for any input.