I run a number of servers that are attached to two different L3 network switches for redundancy. My usual pattern for this is to use L3 links to the switches, and then use OSPF to share a loopback IP from Linux into the switches’ dynamic routing instances. That way, either switch can go down (software upgrades, hardware faults, cleaning up network cables, whatever) and traffic keeps flowing, because I still have at least one path to the server. On some systems, this has worked flawlessly fo...
