I'm trying to setup a simple router to provide failover connectivity. The main connection is via cable and the secondary being DSL. I setup two default routes with the DSL having a metric of 10, so that it goes back to the cable connection once it's back up.
I did echo 10 > /proc/sys/net/ipv4/route/gc_timeout, and it switches over to the DSL when I pull the network cable for the Cable connection. However, this takes a full 60 seconds befor I see a "Destination Unreachable" from ping, and then the 10 seconds (from gc_timeout) to switch to the backup route.
My question is: can I reduce this time from 60 seconds to something more preferable, like, 10 seconds?
Should I try bonding eth1 and eth2? I saw that you can set the MII Polling Interval in ms, but is this after the 60 seconds? I'm trying to get around whatever this 60 seconds is from. I don't know if this is part of the nic driver to wait 60 seconds before notifying the kernel the link is down. Even if that's the case, the phsyical link will be up during a normal scenerio. It's the connection between the cable modem and the ISP that goes down.
Hopefully I'm making sense. I've been racking my brain with this problem for so long that I can't even think straight.
Thanks in advance for any insight.