Diedrich Ehlerding wrote: > I have a question concerning the expected behavior of dm_multipath > connected to an EMC Clariion array. Different versions of multipath > give different results when I disconnect all pathes to the storage. > > I have one server (SuSE SLES10 SP2, 2.6.16.60-0.3, multipath-tools > 0.4.7-34.43) and another one (SLES 11, 2.6.27.19-5-default, 0.4.8- > 40.1). Both versions recognize the Clariion without further setting in > multipath.conf. The settings for the Clariion in multipath -t seem to > be the same (especially queue_if_no_path + no_path_retry 60) > > Trying to setup a software mirror on top, i.e. trying to mirror the > data into a second box, I observed the follwoing diffenrent behavior > between these two versions: > > - on the SLES10 machine, disconnecting the disk in one Clariion results > in IO error, the mirror breaks up, and the use IO continues on the > surviving part of the mirror. This is the behavior which I want, and > which I expected, and this was my understanding of "no_path_retry" - > retry some times, then terminate IO. > > - on the SLES11 machine, the same attempt makes IO hang infinitely. The > messages display that all pathes fail, and then "Entering recovery > mode: max_retries=60" - but then, nothing happens; IOs hang. > Yes, I know. You are triggering Novell bugzilla #485281 Patch is already available from my multipath repository git://git.kernel.org/pub/scm/linux/kernel/git/hare/multipath-tools.git branch sles11 Will be included in the next maintenance update. Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage hare@xxxxxxx +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: Markus Rex, HRB 16746 (AG Nürnberg) -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
