Re: [LSF/MM TOPIC] I_T Nexus loss SCSI error handling
On Mon, Jan 21, 2013 at 3:18 AM, Hannes Reinecke h...@suse.de wrote: The current error handler still uses a 'target reset' (or, rather, bus reset) strategy, although the respective TMF has been obsoleted since SAM-3. SAM-5 defines an I_T nexus loss event instead, which so far has only been implemented in libsas. There has been some discussions on the mailing list, but so far there hasn't been any conclusion. So I would like to discuss a possible implementation of a I_T Nexus loss strategy and how to keep compability with SAM-2 targets. Would this handle the case of a SAS fabric with lots of target devices, where we start to get errors from a single device while IO is proceeding fine to everything else on the fabric? It would be really nice if the Linux stack handled this without escalating to a target reset and host reset, since that disrupts all the IO that is proceeding fine (and which won't do much to fix a target drive that might really be dead). - R. -- To unsubscribe from this list: send the line unsubscribe linux-scsi in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[LSF/MM TOPIC] I_T Nexus loss SCSI error handling
Hi all, here's a topic I'd like to discuss at LSF/MM: SCSI error handling update to handle I_T Nexus loss. The current error handler still uses a 'target reset' (or, rather, bus reset) strategy, although the respective TMF has been obsoleted since SAM-3. SAM-5 defines an I_T nexus loss event instead, which so far has only been implemented in libsas. There has been some discussions on the mailing list, but so far there hasn't been any conclusion. So I would like to discuss a possible implementation of a I_T Nexus loss strategy and how to keep compability with SAM-2 targets. Cheers, Hannes -- Dr. Hannes Reinecke zSeries Storage h...@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) -- To unsubscribe from this list: send the line unsubscribe linux-scsi in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
