[Cluster-devel] unfencing

[David Teigland <teigland@redhat.com>]

On Mon, Feb 23, 2009 at 02:24:13PM -0600, Ryan O'Hara wrote:
> On Mon, Feb 23, 2009 at 01:09:58PM -0600, David Teigland wrote:
> > On Mon, Feb 23, 2009 at 07:52:55PM +0100, Fabio M. Di Nitto wrote:
> > > What can stop a user to run fence_node -U from another node to do remote
> > > (un)fencing?
> > 
> > It would work.  Users can do anything they like, that's beside the point.
> 
> It would not work for scsi reservations. With scsi reservations, an
> unfence operation is as simple a registering with the device(s). It
> cannot be done remotely. A registration exists on an "IT nexus"; the
> relationship between initiator and target. Bottom line is that a
> remote node cannot register another node --- the registration
> (sg_persist command) has to be run on the node that wants to "unfence"
> itself.

OK, thanks, that's good to keep in mind.  The "other scheme" I mentioned
originally where *other* nodes would unfence a node (instead of
self-unfencing) wouldn't work for scsi.

Dave