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Re:true failover?

Posted by: Administrator on October 12, 2006 09:06 PM
I'm in agreement, the solution proposed is not appropriate for failover.

Basically, I am running OSPF on dual eth servers, to provide two optional paths to two cisco's, who in turn peer via bgp with our isps. There's a bit more to it, but that's the gist.

However, I have recently discovered a before unnoticed (doh) but MAJOR problem w/r to dual homing / resiliency with linux.

Quite simply, if the interface goes to a down state (ie the RUNNING flag goes away but the interface remains in ifconfig - eg if you unplug the wire), the ip network for that interface remains in the route table as directly connected.


Seriously, if you think about it, the device will black hole all traffic destined to the network on the down interface, even though it has an alternate path learned via a protocol.
Or more simply, it will route traffic to a network that is on a dead interface.

If anyone has any bright ideas (tried kernel netdev, etc, to no avail) pls advise !

Tried poking around with the netlink api, but gee, why should it be only I who has a linux router that works properly.<nobr> <wbr></nobr>:>


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