On 06/05/2014 01:50 PM, Christoph Hellwig wrote:
I've been looking into support blk-mq/scsi-mq in dm-mpath, but I'm already running into issues with mainline. I created a couple luns (without second path) using iet, and then using the iscsi initiator to access them. But it seems like no I/O is possible through dm-mpath for this simple setup as the kpartx processes spawned by udev already hang. Is dm-mpath (default config, no multipath.conf) support to work for a single path setup, or is this expected behavior?
Hmm. This shouldn't happen.But be aware, that multipath doesn't play well together with systemd currently. I've done plenty of fixes to get it up and running for SLES12; once they've stabilized I'll be sending them mainline.
But for a stable testbed I would recommend against systemd currently.
The easiest bit would be set set up lio in loopback mode, and map two luns pointing to the same device.Does anyone have a good default iet or maybe lio config for dm-mpath testing?
I've attached a small script I'm using for a quick test here. Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage hare suse de +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: J. Hawn, J. Guild, F. Imendörffer, HRB 16746 (AG Nürnberg)