R: [Linux-cluster] 2 Node Cluster - SAN Fencing

[David Teigland]

On Mon, Mar 27, 2006 at 09:23:00AM +0200, Leandro Dardini wrote:
>  
> 
> > -----Messaggio originale-----
> > Da: linux-cluster-bounces at redhat.com 
> > [mailto:linux-cluster-bounces at redhat.com] Per conto di Lon Hohberger
> > Inviato: gioved? 23 marzo 2006 16.06
> > A: linux clustering
> > Oggetto: Re: [Linux-cluster] 2 Node Cluster - SAN Fencing
> > 
> > On Wed, 2006-03-22 at 14:46 -0500, Hendershot, Zach wrote:
> > > Hi,
> > >     I have a 2 node cluster that I'm setting up fencing on (with 
> > > fence_brocade). As a test I bring down the heartbeat network. A few 
> > > seconds pass and BOTH nodes fence each other off of the SAN 
> > (via the 
> > > 2nd network interface on the machines). Should I put the brocade 
> > > switch on the heartbeat network, or is there a better way? Thanks.
> > 
> > 2-node clusters need power fencing.
> 
> Do you mean that fence_brocade like fencing devices are not suitable to
> fence a two node cluster?

In situations where one of the two nodes didn't actually fail you can
get both nodes fencing each other.  With SAN fencing both will disable
each other and neither will be able to access storage, with power fencing
the first one reboots the second so the second doesn't get a chance to
reboot the first.

Dave