I get the impression that issue wasn't network hardware but bad high availability design on fileserver side. Why do GitHub has failover network on same network hardware as primary network? But I am not surprised as I see this at lot of clients that they have failover network on separate VLAN on same network hardware. And, whenever they have network hardware issue, servers run into split brain problems.
The failover network should be totally different physically and logically from primary network. The heartbeat between file servers should be checked through both primary network and failover network. If a server can't be reached by its partner over primary network, it should be gracefully taken offline by partner through failover network.
The failover network should be totally different physically and logically from primary network. The heartbeat between file servers should be checked through both primary network and failover network. If a server can't be reached by its partner over primary network, it should be gracefully taken offline by partner through failover network.