[Linux-cluster] ip-tiebreaker quotes need explainging

[Lon Hohberger]

On Sat, 2006-09-30 at 19:52 -0700, Rick Rodgers wrote:
> Can anyone explain why this is so. Why is it only used on maintaining
> qourum and not startup?
> 
> 
> "The IP tiebreaker is typically used to *maintain* a quorum after a node
> failure, because there are certain network faults in which two nodes may
> see the tiebreaker - but not each other.
> -- Lon"


In certain situations  (ex: ARP storms, switch loops, etc.), it is
possible to see the IP-tiebreaker (an upstream router) but *not* your
peer over the switch.  If this happens to both nodes, you have a split
brain.  I should update the internals big to reflect the 'why'.  You can
change this behavior using cludb.

Note that IP tiebreakers have to be in the cluster communications path -
you can't use heartbeating over a private network and an IP tiebreaker
on another network.

-- Lon