Hello, I'm playing with dual-port NIC driver level link failover: * Driver exposes single network interface to the OS and operates both ports in active-passive failover mode. * Upon Link down event on active port, driver switches active and passive ports transparently for the OS. I'm testing the driver using Linux bridge module: "failover" dual-port NIC connected with two cables back-to-back to eth0 and eth1 which are part of br0 bridge. I simulate link fail with following scenario: * At t0 both eth0 and eth1 port links are UP, traffic is accepted by eth0 and forwarded to br0 * At t1 I manually unplug eth0 cable, causing link to go down. "Failover" driver switches the traffic immediately from eth0 to eth1, while using the same MAC address. * From t1 till t1+12 secs packets are accepted by eth1 but dropped by bridge and not forwarded to br0. * At t1+12 secs bridge starts forwarding packets from eth1 to br0 Hmm... I would expect that eth0 link down event would flush from bridge's table any MAC address associated with the port and that the bridge would start forwarding packets from eth1 to br0 immediately. Why does it take ~12 secs for bridge to learn that MAC address moved from eth0 to eth1 in the described scenario? Thank you for your help, Alexander Indenbaum
