Details
-
Bug
-
Resolution: Fixed
-
Major
-
Lustre 2.4.0, Lustre 2.4.1
-
None
-
Lustre 2.4.1 RHEL6 2.6.32-358.18.1.el6_lustre.x86_64
-
4
-
11777
Description
"lfs_migrate -y" aborts with this error
cannot swap layouts between <filename> and a volatile file (Operation not permitted)
This seems to happen for all files. The lfs_migrate operation aborts on the first file.
Attachments
Issue Links
Activity
Patch to allow layout swap for IGIF file is at http://review.whamcloud.com/8737.
Humm thanks, I understand I better had to read LU-4392 sub-task and learn more about LFSCK behavior than to ask, sorry !!
So now, do we really need to detect such files with a wrongly assigned IGIF by LFSCK (to be fixed in LU-4392 sub-task) ?? Because if not, fix for this ticket's original issue could simply be to add fid_is_igif() test for both files having their layouts swapped, in mdd_layout_swap_allowed().
I may miss some special cases about files with IGIF here since you wrote about "internal system files by using their (internal) IGIF FIDs" ??…
I will also work on the MDT volatile object leak upon layouts swap failure, may be as part as a new ticket.
I created the IGIF files under 1.8 and upgraded to 2.x. You could also get the same effect by mounting a 2.4 MDT as ldiskfs, deleting the "lma" xattr, then rounding and running LFSCK to fix the OI.
Sorry to be late, but I am back on this one.
Andreas, sorry to ask but can you explain me how the files created in MDT root-directory have an IGIF assigned ??
I also confirm that as part of LU-3834, and fault-injection during layouts-swap to verify patch behavior, I reproduce the volatile object leak (inode links number is 1 and e2fsck detects "Unattached inode") on MDT. In my case, and for one layouts-swap forced error, I see one orphan inode with ".^L^S^T^R:VOLATILE"/LUSTRE_VOLATILE_HDR linkEA but also one with "i_am_nobody", did you also find this ?
But anyway, this clearly indicate that there is something to address and fix upon layouts-swap error.
Uploaded a patch to correctly handle "lfs migrate" failure in lfs_migrate and do fallback to rsync copy+rename:
http://review.whamcloud.com/8616
This is not a complete solution to the problem here, but is useful in any case.
Bruno, yes after the migration failure the original file is still accessible. Ideally, if the MDD could verify if the object is in the namespace then that would be a good way to know if it can be migrated or not. I think allowing to migrate IGIF FIDs is a potential problem, but not worse than other issues a client might have, so that would be a solution for 2.6 if no others are available.
Andreas,
After the failure, is the original file still accessible ?
Also, since it appears the main problem for this ticket is that trying "lfs migrate" on 1.8 files with IGIF fids will fail and leak volatile objects on MDT, why not 1st change test in mdd_layout_swap_allowed() by adding/allowing also fid_is_igif() files ? Then we will address the special cases of system/ROOT files and the failure/recovery.
Or do you still think all cases must be handled in "lfs migrate" by switching to rsync if not a system/ROOT file, and the leak to be addressed separately ?
But finally may be it is related to LU-3834, after my recent discovery there that the layouts swap-back upon failure may not work as expected!
Andreas, LU-3834 is about how to handle/recover-from any layout swap failures during HSM Restore ops and avoid leaving file in inconsistent state, this ticket is for a specific condition and consequence. I will try to push a patch soon based on your already+very detailled analysis, thanks !!
Bruno, does the layout swap failure here have any relation to LU-3834? I saw many leaked objects after failures calling "lfs migrate" on an IGIF file.
I also see that the failure in "lfs migrate" is causing volatile inodes to be leaked on the MDT. I see:
e2fsck 1.42.7.wc1 (12-Apr-2013) Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Unattached inode 116 Connect to /lost+found? no Unattached inode 117 Connect to /lost+found? no Unattached inode 118 Connect to /lost+found? no Unattached inode 409 Connect to /lost+found? no
The unattached inodes look like:
debugfs 1.42.7.wc2 (12-Apr-2013) debugfs: stat <116> Inode: 116 Type: regular Mode: 0644 Flags: 0x0 Generation: 2124528570 Version: 0x00000001:00001b6d User: 0 Group: 0 Size: 0 File ACL: 0 Directory ACL: 0 Links: 1 Blockcount: 0 Fragment: Address: 0 Number: 0 Size: 0 ctime: 0x5296625c:00000000 -- Wed Nov 27 14:21:32 2013 atime: 0x52966270:00000000 -- Wed Nov 27 14:21:52 2013 mtime: 0x52966270:00000000 -- Wed Nov 27 14:21:52 2013 crtime: 0x5296625c:087ac7fc -- Wed Nov 27 14:21:32 2013 Size of extra inode fields: 28 Extended attributes stored in inode body: lma = "00 00 00 00 00 00 00 00 00 04 00 00 02 00 00 00 45 07 00 00 00 00 00 00 " (24) lma: fid=[0x200000400:0x745:0x0] compat=0 incompat=0 link = "df f1 ea 11 01 00 00 00 3a 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 22 00 00 00 02 00 00 00 07 00 00 00 01 00 00 00 00 2e 0c 13 14 12 3a 56 4f 4c 41 54 49 4c 45 3a 3a " (58) lov = "d0 0b d1 0b 01 00 00 00 45 07 00 00 00 00 00 00 00 04 00 00 02 00 00 00 00 00 10 00 01 00 01 00 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 02 00 00 00 " (56) BLOCKS:
where the "link" xattr is the "^.L^S^T^R:VOLATILE" string.
I wonder if the -EPERM error seen on non-IGIF files is due to some file ownership problem like
LU-3826or similar?if ((attr1->la_uid != attr2->la_uid) || (attr1->la_gid != attr2->la_gid)) RETURN(-EPERM);This will fail if lfs_migrate is not creating the file with the same ownership as the original file? If lfs_migrate is running as root, then it should be able to fchown() the file after it is created. The actual permissions don't matter, because the temporary file will be deleted, but this is proof that the caller of the migrate has permission to do this swap.