[Ocfs2-users] Catatonic nodes under SLES10

[Joel Becker]

On Tue, Apr 10, 2007 at 07:06:02PM +0200, Eckenfels. Bernd wrote:
> > It's not at all about what your past activitiy was like. We fence to
> prevent future activity.
> 
> There is a lot you can do instead, including SCSI plugging the device o
> just setting a RO flag in the filesystem (remount-ro-on-error style).
> There might be times when it is needed to shoot the node in the head,
> but those are not handled by the self-panic anyway...

	By the time you determine you need a node to fence, you do not
know what I/O it has in its pipeline.  Any I/O that is below the request
queue can't reliably be stopped in Linux.  If that I/O goes out after
other nodes have decided the node is gone, it is corruption.  This is
why fencing has to be absolute.

Joel

-- 

"War doesn't determine who's right; war determines who's left."

Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker at oracle.com
Phone: (650) 506-8127