[Linux-HA] Geographic Redundancy?

[Werner Fischer]

On Tue, 2006-09-12 at 14:45 -0400, Jiann-Ming Su wrote:
> [...]
> Each server has two NICs.  Each NIC will be connected to a different
> router, so there will be multiple paths between the nodes.  We're
> concerned about a "hangman" situation where communication between both
> nodes goes down and the services we're monitoring with Heartbeat come
> up on both nodes.
> 
> Is there an easy way to configure 2.0.x without CRM so that in a state
> of confusion, only the primary node stays up?
Unfortunately it is not that easy I think. If you have two nodes,
sitting at two different sites, they cannot easily distinguish between
the other node beeing dead or all communication paths being dead.
You can find a discussion about some basics on that in my thesis
http://www.wefi.net/thesis/diploma_thesis_werner_fischer.pdf
(Chapter 3, Disaster Recovery Basics)

hth,
Werner