Hi Phil, On Wed, 2012-07-11 at 16:30 -0400, Phil Frost wrote: > I've been attempting to create a HA iSCSI target with LIO and Pacemaker. > I was encountering a kernel oops on migrations, and found this thread in > the archives from April, which looks like the same problem: > > http://comments.gmane.org/gmane.linux.scsi.target.devel/1568?set_cite=hide > > It sounds like the OP was able to work around the problem by modifying > the pacemaker resource agent, however few details about how. My bust > guess turned out to be less trivial than I thought. The pacemaker lists > don't seem aware of the issue. > Mmmm, feel tree to forward this along to the pacemaker folks. > Has anyone else encountered this issue and willing to share a solution? > So the main workaround with iscsi-target TPG demo-mode operation + active I/O shutdown is mentioned here: http://permalink.gmane.org/gmane.linux.scsi.target.devel/1819 The key bit is: "What I meant here is that the important part is currently disabling the TPG before bringing down the TPG LUN associated with the backend with active IO, ahead of the backend itself. This will shutdown all active iSCSI sessions (and hence outstanding I/Os) to underlying backend devices, and after it's completed it will be safe to remove an associated backend device." Which means is that the very first thing you want to do is: echo 0 > /sys/kernel/config/target/iscsi/$TARGETNAME/tpgt_$TPGT/enable for each iscsi-target endpoint before tearing down TPG LUNs in /iscsi/, and before tearing down TCM device backends. Doing this first will ensure that all active sessions (and I/O) are stopped, and that no new sessions may login while bringing down the individual endpoint. > Alternately, any progress on a fix for the underlying bug? > This item is still on my TODO, but unfortunately it's not been resolved just yet. I strongly recommend if your going to use TPG demo-mode with H/A + active I/O shutdown, to fix up the cluster RA script to disable the TPG before shutdown. --nab -- To unsubscribe from this list: send the line "unsubscribe target-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
