[Lustre-discuss] recovering formatted OST
Bernd Schubert
bernd.schubert at fastmail.fm
Tue Oct 26 09:38:34 PDT 2010
Hello Lisa,
OST-index and the fsname identify the OST for the MGS, MGS and clients.
If you reformat an OST and you do not re-use the old index, it will leave a
hole, as the new OST gets another index. And OST holes are an uncommon
scenario, it often triggers some bugs...
Cheers,
Bernd
On Tuesday, October 26, 2010, Lisa Giacchetti wrote:
> Wojciech,
> since you have successfully done step #4 can you tell me what is use
> in the reformat for the old index id?
> I tried to do this a few weeks ago was not succsessful at reformatting
> an ost with the old index because
> I am not clear on what the index is. I asked on this list at that
> time for input and did not get much.
> If you could provide the exact command you used that would be good too.
>
> lisa
>
> On 10/26/10 10:31 AM, Wojciech Turek wrote:
> > Since some of our users started to recover their data from backups or
> > by other means (rerunning jobs etc) into the original locations I
> > don't think it would be good idea to put the recovered OST back in
> > service as it is, as that may cause some of users new files to be
> > overwritten by the recovered files.
> >
> > To avoid that scenario I decided to reformat the old OST and put it
> > back into filesystem as empty.
> > 1) First I have created a backup of the recovered object files
> > 2) then using lfs find and lfs getstripe on the client I created a
> > list of files and object ids from the formatted OST
> > 3) using backup from point 1 and information from point 2 I copied
> > objects to a new location on the filesystem and renamed them to their
> > original name. Now users can interrogate those files and choose which
> > they want to keep.
> > 4) I reformatted old OST with old index id and old label
> >
> >
> > Before I mount that OST into filesystem I want to make sure that MDS
> > detects it as empty OST and does not try to recreate missing objects.
> > Would it be enough to remove lov_objid from MDT and let it create new
> > lov_objid based on information from OSTs, or do I need to first unlink
> > all missing files from the client?
> >
> > Best regards,
> >
> > Wojciech
> >
> > On 26 October 2010 05:36, Wojciech Turek <wjt27 at cam.ac.uk
> >
> > <mailto:wjt27 at cam.ac.uk>> wrote:
> > Bernd, I would like to clarify if I understood you suggestion
> > correctly:
> >
> > 1) create a new OST but using old index and old label
> > 2) mount it as ldiskfs and copy recovered objects (using tar or
> > rsync with xattrs support) from the old OST to the new OST
> > 3) run --writeconf on MDT and OST of that filesystem
> > 4) mount MDT and all OSTs
> >
> >
> > I guess I could do it also that way:
> >
> > 1) backup restored object using tar or rsync with xattrs support
> > 2) format old OST with old index and old label
> > 3) restore Objects from the backup
> >
> > Do you think that would work?
> >
> > Best regards,
> >
> > Wojciech
> >
> >
> >
> > On 22 October 2010 18:52, Bernd Schubert
> > <bernd.schubert at fastmail.fm <mailto:bernd.schubert at fastmail.fm>>
> >
> > wrote:
> > Hmm, I would probably format a small fake device on a ramdisk
> > and copy files
> > over, run tunefs --writeconf /mdt and then start everything
> > (inlcuding all
> > OSTs) again.
> >
> >
> > Cheers,
> >
> > On Friday, October 22, 2010, Wojciech Turek wrote:
> > > I have tried Bernd's suggestion and it seem to have worked,
> >
> > after running
> >
> > > e2fsck -D ll_recover_lost_found_objs didn't cause kernel
> >
> > panic but moved a
> >
> > > number of objects to O directory. Problem is that I do not
> >
> > have last_rcvd
> >
> > > file so the OST has no index at the moment. What would be
> >
> > the next step to
> >
> > > enable access to those files in the filesystem?
> > >
> > > Best regards,
> > >
> > > Wojciech
> > >
> > > On 22 October 2010 17:15, Andreas Dilger
> >
> > <andreas.dilger at oracle.com <mailto:andreas.dilger at oracle.com>>
> >
> > wrote:
> > > > On 2010-10-22, at 5:42, Bernd Schubert
> >
> > <bernd.schubert at fastmail.fm
> >
> > <mailto:bernd.schubert at fastmail.fm>> wrote:
> > > > > Hmm, e2fsck didn't catch that? rec_len is the length of
> >
> > a directory
> >
> > > > entry, so
> > > >
> > > > > after how many bytes the next entry follows.
> > > >
> > > > I agree that e2fsck should have caught that.
> > > >
> > > > > You can try to force e2fsck to do
> > > > > something about that: e2fsck -D
> > > >
> > > > No, I would recommend against using -D at this point. That
> >
> > will cause it
> >
> > > > to re-write the directory contents, and given that the
> >
> > filesystem was
> >
> > > > previously corrupted I would prefer making as few changes
> >
> > as possible
> >
> > > > before the data is estranged.
> > > >
> > > > Wojciech,
> > > > note that if you are able to mount the filesystem you
> >
> > could just copy all
> >
> > > > of the objects (with xattrs!) from lost+found on the bad
> >
> > filesystem,
> >
> > > > along with the last_rcvd file (if you can find it) into a
> >
> > new ldiskfs
> >
> > > > filesystem and then run ll_recover_lost_found_objs on that.
> > > >
> > > > > On Friday, October 22, 2010, Wojciech Turek wrote:
> > > > >> Ok, removing and recreating the journal fixed that
> >
> > problem and I am
> >
> > > > >> able
> > > >
> > > > to
> > > >
> > > > >> mount device as ldiskfs filesystem. Now I hit another
> >
> > wall when trying
> >
> > > > to
> > > >
> > > > >> run ll_recover_lost_found_objs
> > > > >> When I first time run ll_recover_lost_found_objs -d
> > > > >> /mnt/ost/lost+found
> > > >
> > > > it
> > > >
> > > > >> only creates the O dir and exits. When I repeat this
> >
> > command again
> >
> > > > kernel
> > > >
> > > > >> panics. Any idea what could be the problem here?
> > > > >>
> > > > >>
> > > > >> LDISKFS-fs error (device dm-4): ldiskfs_readdir: bad
> >
> > entry in
> >
> > > > >> directory #6831: rec_len is smaller than minimal -
> >
> > offset=0, inode=0,
> >
> > > > >> rec_len=0, name_len=0
> > > > >> Aborting journal on device dm-4.
> > > > >> Unable to handle kernel NULL pointer dereference at
> >
> > 0000000000000000
> >
> > > > RIP:
> > > > >> [<ffffffff88033448>]
> > :
> > :jbd:journal_commit_transaction+0xc5b/0x12db
> > :
> > > > >> PGD 1a118d067 PUD 1ce7e7067 PMD 0
> > > > >> Oops: 0002 [1] SMP
> > > > >> last sysfs file: /class/infiniband_mad/umad0/port
> > > > >> CPU 3
> > > > >> Modules linked in: ldiskfs(U) crc16(U) autofs4(U)
> >
> > hidp(U) l2cap(U)
> >
> > > > >> bluetooth(U) rdma_ucm(U) rdma_cm(U) iw_cm(U) ib_addr(U)
> >
> > ib_ipoib(U)
> >
> > > > >> ipoib_helper(U) ib_cm(U) ipv6(U) xfrm_nalgo(U)
> >
> > crypto_api(U)
> >
> > > > ib_uverbs(U)
> > > >
> > > > >> ib_umad(U) mlx4_vnic(U) mlx4_vnic_helper(U) ib_sa(U)
> >
> > ib_mthca(U)
> >
> > > > mptctl(U)
> > > >
> > > > >> dm_mirror(U) video(U) backlight(U) sbs(U)
> >
> > power_meter(U) hwmon(U)
> >
> > > > i2c_ec(U)
> > > >
> > > > >> i2c_core(U) dell_wmi(U) wmi(U) button(U) battery(U)
> >
> > asus_acpi(U)
> >
> > > > >> acpi_memhotplug(U) ac(U) parport_pc(U) lp(U) parport(U)
> >
> > sr_mod(U)
> >
> > > > cdrom(U)
> > > >
> > > > >> mlx4_ib(U) ib_mad(U) ib_core(U) joydev(U) mlx4_core(U)
> >
> > usb_storage(U)
> >
> > > > >> pcspkr(U) shpchp(U) serio_raw(U) i5000_edac(U)
> >
> > edac_mc(U) dm_raid45(U)
> >
> > > > >> dm_message(U) dm_region_hash(U) dm_log(U) dm_mod(U)
> >
> > dm_mem_cache(U)
> >
> > > > nfs(U)
> > > >
> > > > >> lockd(U) fscache(U) nfs_acl(U) sunrpc(U) mptsas(U)
> >
> > mptscsih(U)
> >
> > > > mptbase(U)
> > > >
> > > > >> scsi_transport_sas(U) mppVhba(U) megaraid_sas(U)
> >
> > mppUpper(U) sg(U)
> >
> > > > >> sd_mod(U) scsi_mod(U) bnx2(U) ext3(U) jbd(U)
> >
> > uhci_hcd(U) ohci_hcd(U)
> >
> > > > >> ehci_hcd(U) Pid: 11360, comm: kjournald Tainted: G
> > > > >> 2.6.18-194.3.1.el5_lustre.1.8.4 #1
> > > > >> RIP: 0010:[<ffffffff88033448>] [<ffffffff88033448>]
> > > > >>
> > > > >> :jbd:journal_commit_transaction+0xc5b/0x12db
> > > > >>
> > > > >> RSP: 0018:ffff8101c6481d90 EFLAGS: 00010246
> >
> > > > >> RAX: 0000000000000000 RBX: 0000000000000000 RCX:
> > 00000000ffffffff
> >
> > > > >> RDX: 0000000000000000 RSI: ffff8101e9dab0c0 RDI:
> > ffff81022fa46000
> >
> > > > >> RBP: ffff81022fa46000 R08: ffff81022fa46068 R09:
> > 0000000000000000
> >
> > > > >> R10: ffff810105925b20 R11: 00000000fffffffa R12:
> > 0000000000000000
> >
> > > > >> R13: 0000000000000000 R14: ffff8101e9dab0c0 R15:
> > 0000000000000000
> >
> > > > >> FS: 0000000000000000(0000) GS:ffff810107b9a4c0(0000)
> > > > >> knlGS:0000000000000000 CS: 0010 DS: 0018 ES: 0018 CR0:
> >
> > > > >> 000000008005003b CR2: 0000000000000000 CR3:
> > 00000001eaffb000 CR4:
> > > > >> 00000000000006e0 Process kjournald (pid: 11360, threadinfo
> > > > >> ffff8101c6480000, task ffff81021c14c0c0)
> > > > >> Stack: ffff8101a61b9000 000000002b8263c0 ffffffff00000000
> > > >
> > > > 0000000000000000
> > > >
> > > > >> 0000113b00000001 0000000000000013 0000000000000000
> >
> > 0000000000000111
> >
> > > > >> 0000000000000000 0000000000000000 0000000001282dd7
> >
> > 00000000000020dd
> >
> > > > >> Call Trace:
> > > > >> [<ffffffff8003da91>] lock_timer_base+0x1b/0x3c
> > > > >> [<ffffffff8004b347>] try_to_del_timer_sync+0x7f/0x88
> > > > >> [<ffffffff88037386>] :jbd:kjournald+0xc1/0x213
> > > > >> [<ffffffff800a0ab2>] autoremove_wake_function+0x0/0x2e
> > > > >> [<ffffffff800a089a>] keventd_create_kthread+0x0/0xc4
> > > > >> [<ffffffff880372c5>] :jbd:kjournald+0x0/0x213
> > > > >> [<ffffffff800a089a>] keventd_create_kthread+0x0/0xc4
> > > > >> [<ffffffff80032890>] kthread+0xfe/0x132
> > > > >> [<ffffffff8005dfb1>] child_rip+0xa/0x11
> > > > >> [<ffffffff800a089a>] keventd_create_kthread+0x0/0xc4
> > > > >> [<ffffffff8014bcf4>] deadline_queue_empty+0x0/0x23
> > > > >> [<ffffffff80032792>] kthread+0x0/0x132
> > > > >> [<ffffffff8005dfa7>] child_rip+0x0/0x11
> > > > >>
> > > > >>
> > > > >> Code: f0 0f ba 33 01 e8 42 fc 02 f8 8b 03 a8 04 75 07
> >
> > 8b 43 58 85
> >
> > > > >> RIP [<ffffffff88033448>]
> > :
> > :jbd:journal_commit_transaction+0xc5b/0x12db
> > :
> > > > >> RSP <ffff8101c6481d90>
> > > > >> CR2: 0000000000000000
> > > > >> <0>Kernel panic - not syncing: Fatal exception
> > > > >>
> > > > >> On 22 October 2010 03:09, Andreas Dilger
> >
> > <andreas.dilger at oracle.com <mailto:andreas.dilger at oracle.com>>
> >
> > > > wrote:
> > > > >>> On 2010-10-21, at 18:44, Wojciech Turek
> >
> > <wjt27 at cam.ac.uk <mailto:wjt27 at cam.ac.uk>> wrote:
> > > > >>> fsck has finished and does not find any more errors to
> >
> > correct.
> >
> > > > >>> However when I try to mount the device as ldiskfs
> >
> > kernel panics with
> >
> > > > >>> following message:
> > > > >>>
> > > > >>> Assertion failure in cleanup_journal_tail() at
> > > > >>> fs/jbd/checkpoint.c:459: "blocknr != 0"
> > > > >>>
> > > > >>>
> > > > >>> Hmm, not sure, maybe your journal is broken? You can
> >
> > delete it with
> >
> > > > >>> "tune2fs -O ^has_journal" (maybe after running e2fsck
> >
> > again to clear
> >
> > > > the
> > > >
> > > > >>> journal), then re-create it with "tune2fs -j".
> > > > >>>
> > > > >>> ----------- [cut here ] --------- [please bite here ]
> >
> > ---------
> >
> > > > >>> Kernel BUG at fs/jbd/checkpoint.c:459
> > > > >>> invalid opcode: 0000 [1] SMP
> > > > >>> last sysfs file: /class/infiniband_mad/umad0/
> > > > >>> port
> > > > >>> CPU 2
> > > > >>> Modules linked in: obdfilter(U) fsfilt_ldiskfs(U)
> >
> > ost(U) mgc(U)
> >
> > > > >>> ldiskfs(U) crc16(U) lustre(U) lov(U) mdc(U) lquota(U)
> >
> > osc(U)
> >
> > > > ksocklnd(U)
> > > >
> > > > >>> ko2iblnd(U) ptlrpc(U) obdclass(U) lnet(U) lvfs(U)
> >
> > libcfs(U)
> >
> > > > >>> autofs4(U) hidp(U) l2cap(U) bluetooth(U) rdma_ucm(U)
> >
> > rdma_cm(U)
> >
> > > > >>> iw_cm(U)
> > > >
> > > > ib_addr(U)
> > > >
> > > > >>> ib_ipoib(U) ipoib_helper(U) ib_cm(U) ipv6(U)
> > > > >>> xfrm_nalgo(U)
> > > >
> > > > crypto_api(U)
> > > >
> > > > >>> ib_uverbs(U) ib_umad(U) mlx4_vnic(U)
> >
> > mlx4_vnic_helper(U) ib_sa(U)
> >
> > > > >>> ib_mthca(U) mptctl(U) dm_mirror(U) video(U)
> >
> > backlight(U) sbs(U)
> >
> > > > >>> power_meter(U) hwmon(U) i2c_ec(U) i2c_core(U)
> >
> > dell_wmi(U) wmi(U)
> >
> > > > >>> button(U) battery(U) asus_acpi(U) acpi_memhotplug(U)
> > > > >>> ac(U)
> > > >
> > > > parport_pc(U)
> > > >
> > > > >>> lp(U) parport(U) sr_mod(U) cdrom(U) mlx4_ib(U)
> >
> > ib_mad(U) ib_core(U)
> >
> > > > >>> joydev(U) mlx4_core(U) usb_storage(U) shpchp(U)
> >
> > i5000_edac(U)
> >
> > > > edac_mc(U)
> > > >
> > > > >>> serio_raw(U) pcspkr(U) dm_raid45(U) dm_message(U)
> >
> > dm_region_hash(U)
> >
> > > > >>> dm_log(U) dm_mod(U) dm_mem_cache(U) nfs(U) lockd(U)
> >
> > fscache(U)
> >
> > > > >>> nfs_acl(U) sunrpc(U) mptsas(U) mptscsih(U) mptbase(U)
> > > > >>> scsi_transport_sas(U) mppVhba(U) megaraid_sas(U)
> >
> > mppUpper(U) sg(U)
> >
> > > > >>> sd_mod(U) scsi_mod(U) bnx2(U) ext3(U) jbd(U)
> >
> > uhci_hcd(U) ohci_hcd(U)
> >
> > > > >>> ehci_hcd(U) Pid: 13891, comm: mount Tainted: G
> >
> > > > >>> 2.6.18-194.3.1.el5_lustre.1.8.4 #1 RIP:
> > 0010:[<ffffffff88034a95>]
> >
> > > > >>> [<ffffffff88034a95>]
> > > > >>>
> > > > >>> :jbd:cleanup_journal_tail+0x9d/0x118
> > > > >>>
> > > > >>> RSP: 0018:ffff81016f00da68 EFLAGS: 00010286
> >
> > > > >>> RAX: 000000000000005a RBX: ffff81012ca12c00 RCX:
> > ffffffff80311da8
> >
> > > > >>> RDX: ffffffff80311da8 RSI: 0000000000000000 RDI:
> > ffffffff80311da0
> >
> > > > >>> RBP: 0000000000000000 R08: ffffffff80311da8 R09:
> > 0000000000000001
> >
> > > > >>> R10: 0000000000000000 R11: 0000000000000080 R12:
> > 0000000000000002
> >
> > > > >>> R13: ffff81012ca12d4c R14: ffff81012ca12c24 R15:
> > ffff81017a8d7400
> >
> > > > >>> FS: 00002abd7cef1f70(0000) GS:ffff810107b9acc0(0000)
> > > > >>> knlGS:0000000000000000
> > > > >>> CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> >
> > > > >>> CR2: 000000000042b000 CR3: 000000012813f000 CR4:
> > 00000000000006e0
> >
> > > > >>> Process mount (pid: 13891, threadinfo
> >
> > ffff81016f00c000, task
> >
> > > > >>> ffff81022e1b7820)
> > > > >>> Stack: 0000000000000000 ffff81012ca12c00
> > > > >>> ffff81017a8d7400 ffffffff88037690
> > > > >>>
> > > > >>> ffff81012ca12c00 ffff8102034ff000 ffff81017a8d7400
> >
> > 0000000000000000
> >
> > > > >>> ffff8102034ff000 ffffffff88a9be56 0000000001000000
> >
> > ffff8101bf788000
> >
> > > > >>> Call Trace:
> > > > >>> [<ffffffff88037690>] :jbd:journal_flush+0xbe/0x248
> > > > >>> [<ffffffff88a9be56>]
> > > > >>>
> > > > >>> :ldiskfs:ldiskfs_mark_recovery_complete+0x36/0x90
> > > > >>>
> > > > >>> [<ffffffff88aa02e0>]
> > :
> > :ldiskfs:ldiskfs_fill_super+0x1790/0x1950
> > :
> > > > >>> [<ffffffff800eccd2>] get_filesystem+0x12/0x3b
> > > > >>> [<ffffffff800e343e>] test_bdev_super+0x0/0xd
> > > > >>> [<ffffffff88a9eb50>]
> > :
> > :ldiskfs:ldiskfs_fill_super+0x0/0x1950
> > :
> > > > >>> [<ffffffff800e43fd>] get_sb_bdev+0x10a/0x16c
> > > > >>> [<ffffffff800e3d9a>] vfs_kern_mount+0x93/0x11a
> > > > >>> [<ffffffff800e3e63>] do_kern_mount+0x36/0x4d
> > > > >>> [<ffffffff800ee601>] do_mount+0x6a9/0x719
> > > > >>> [<ffffffff800090d2>] __handle_mm_fault+0x96f/0xfaa
> > > > >>> [<ffffffff8002c9e0>] mntput_no_expire+0x19/0x89
> > > > >>> [<ffffffff8000a72a>] __link_path_walk+0xf1e/0xf42
> > > > >>> [<ffffffff800220ce>] __up_read+0x19/0x7f
> > > > >>> [<ffffffff80066b88>] do_page_fault+0x4fe/0x874
> > > > >>> [<ffffffff8002c9e0>] mntput_no_expire+0x19/0x89
> > > > >>> [<ffffffff8000ea45>] link_path_walk+0xa6/0xb2
> > > > >>> [<ffffffff800cc329>] zone_statistics+0x3e/0x6d
> > > > >>> [<ffffffff8000f2cf>] __alloc_pages+0x78/0x308
> > > > >>> [<ffffffff8004c68e>] sys_mount+0x8a/0xcd
> > > > >>> [<ffffffff8005d28d>] tracesys+0xd5/0xe0
> > > > >>>
> > > > >>> Code: 0f 0b 68 3a 94 03 88 c2 cb 01 44 39 a3 58 01 00
> >
> > 00 75 0e c7
> >
> > > > >>> RIP [<ffffffff88034a95>]
> > :
> > :jbd:cleanup_journal_tail+0x9d/0x118
> > :
> > > > >>> RSP <ffff81016f00da68>
> > > > >>> <0>Kernel panic - not syncing: Fatal exception
> > > > >>>
> > > > >>> Any idea how to fix this?
> > > > >>>
> > > > >>> Many thanks
> > > > >>>
> > > > >>> Wojciech
> > > > >>>
> > > > >>>
> > > > >>> On 21 October 2010 17:54, Wojciech Turek <
> >
> > <wjt27 at cam.ac.uk <mailto:wjt27 at cam.ac.uk>>
> >
> > > > >>> wjt27 at cam.ac.uk <mailto:wjt27 at cam.ac.uk>> wrote:
> > > > >>>> Thanks Ken, that worked.
> > > > >>>>
> > > > >>>>
> > > > >>>> On 21 October 2010 17:39, Ken Hornstein <
> >
> > <kenh at cmf.nrl.navy.mil <mailto:kenh at cmf.nrl.navy.mil>>
> >
> > > > >>>> kenh at cmf.nrl.navy.mil <mailto:kenh at cmf.nrl.navy.mil>>
> >
> > wrote:
> > > > >>>>>> Now I have another problem. After last segfault I
> >
> > can not restart
> >
> > > > the
> > > >
> > > > >>>>> fsck
> > > > >>>>>
> > > > >>>>>> due to MMP.
> > > > >>>>>> [...]
> > > > >>>>>> Also when I try to access filesystem via debugfs it
> >
> > fails:
> > > > >>>>>> debugfs -c -R 'ls' /dev/scratch2_ost16vg/ost16lv
> > > > >>>>>> debugfs 1.41.10.sun2 (24-Feb-2010)
> > > > >>>>>> /dev/scratch2_ost16vg/ost16lv: MMP: fsck being run
> >
> > while opening
> >
> > > > >>>>> filesystem
> > > > >>>>>
> > > > >>>>>> ls: Filesystem not open
> > > > >>>>>>
> > > > >>>>>> Is there a way to clear teh MMP flag so it allows
> >
> > fsck to run?
> >
> > > > >>>>> You want tune2fs -f -E clear-mmp
> > > > >>>>>
> > > > >>>>> --Ken
> >
> > _______________________________________________
> > Lustre-discuss mailing list
> > Lustre-discuss at lists.lustre.org
> > http://lists.lustre.org/mailman/listinfo/lustre-discuss
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