MAC addr takeover

Jim Trocki trockij at
Sat Oct 17 11:16:27 MDT 1998

On Sat, 17 Oct 1998, Cary B. O'Brien wrote:

> I said switch, I should have said router.


>  I'm assuming [1] that you have
> a situation where you've got server A (main) and server B  (backup) on the
> same lan.  Server B monitors server A.  If it fails to respond server B brings
> up the IP address clients use to access the service.  Then it (somehow) clears
> the arp cache on the router that connects the lan with the servers to the
> outside world.

In this situation, I would hope that at least the router is smart enough
to properly update its ARP cache if a gratuitous ARP is sent out when
server B takes over. Of course my assumption that most dedicated routers
(like Ciscos) follow the ARP spec more closely than the average client
(like win95) quite possibly is incorrect :)

> [1] Of course, the lan itself and the router are single points of failure.  Is
> this my confusion?  

Are you confused by this?

More information about the Linux-HA mailing list