Neil, Thanks for the quick suggestion, the hang seems to happen even with the zpool set failmode=continue <pool> option.
Any other way to recover from the hang ? thanks and regards, Karthik On 10/15/08 22:03, Neil Perrin wrote: > Karthik, > > The pool failmode property as implemented governs the behaviour when all > the devices needed are unavailable. The default behaviour is to wait > (block) until the IO can continue - perhaps by re-enabling the device(s). > The behaviour you expected can be achieved by "zpool set > failmode=continue <pool>", > as shown in the link you indicated below. > > Neil. > > On 10/15/08 22:38, Karthik Krishnamoorthy wrote: >> Hello All, >> >> Summary: >> ~~~~~~~~ >> cp command for mirrored zfs hung when all the disks in the mirrored >> pool were unavailable. >> Detailed description: >> ~~~~~~~~~~~~~~~~~~~~~ >> The cp command (copy a 1GB file from nfs to zfs) hung when all >> the disks >> in the mirrored pool (both c1t0d9 and c2t0d9) were removed physically. >> NAME STATE READ WRITE CKSUM >> test ONLINE 0 0 0 >> mirror ONLINE 0 0 0 >> c1t0d9 ONLINE 0 0 0 >> c2t0d9 ONLINE 0 0 0 >> We think if all the disks in the pool are unavailable, cp command >> should >> fail with error (not cause hang). >> Our request: >> ~~~~~~~~~~~~ >> Please investigate the root cause of this issue. >> >> How to reproduce: >> ~~~~~~~~~~~~~~~~~ >> 1. create a zfs mirrored pool >> 2. execute cp command from somewhere to the zfs mirrored pool. >> 3. remove the both of disks physically during cp command working >> = hang happen (cp command never return and we can't kill cp >> command) >> >> One engineer pointed me to this page >> http://opensolaris.org/os/community/arc/caselog/2007/567/onepager/ >> and indicated that if all the mirrors are removed zfs enters a hang >> like state to prevent the kernel from going into a panic mode and >> this type of feature would be an RFE. >> >> My questions are >> >> Are there any documentation of the "mirror" configuration of zfs that >> explains what happens when the underlying >> drivers detect problems in one of the mirror devices? >> >> It seems that the traditional views of "mirror" or "raid-2" would >> expect that the >> mirror would be able to proceed without interruption and that does >> not seem to be this case in ZFS. >> What is the purpose of the mirror, in zfs? Is it more like an instant >> backup? If so, what can the user do to recover, when there is an >> IO error on one of the devices? >> >> >> Appreciate any pointers and help, >> >> Thanks and regards, >> Karthik >> _______________________________________________ >> zfs-discuss mailing list >> zfs-discuss@opensolaris.org >> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
