Thanks for the reply guys... The device in question is a ReadyNAS Pro 6, which happens to be running Linux :) I actually saw some issues with e2fsck 1.42.3 earlier this year: ***** File system check forced at Fri Apr 26 20:08:38 WEST 2013 ***** fsck 1.41.14 (22-Dec-2010) e2fsck 1.42.3 (14-May-2012) Pass 1: Checking inodes, blocks, and sizes Inode 4195619, i_blocks is 3135728, should be 3135904. Fix? yes Running additional passes to resolve blocks claimed by more than one inode... Pass 1B: Rescanning for multiply-claimed blocks Multiply-claimed block(s) in inode 4195619: 167904376 167904377 167904378 167904379 167904380 167904381 167904382 167904383 167904384 167904385 167904386 167949296 167949297 167949298 167949299 167949300 167949301 167949302 167949303 167949304 167949305 167949306 Pass 1C: Scanning directories for inodes with multiply-claimed blocks Pass 1D: Reconciling multiply-claimed blocks (There are 1 inodes containing multiply-claimed blocks.) File /PREMIER/Premier Automation Purchase OrdersApp V18.5.mdb (inode #4195619, mod time Fri Apr 26 20:07:42 2013) has 22 multiply-claimed block(s), shared with 0 file(s): Multiply-claimed blocks already reassigned or cloned. Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information /dev/c/c: ***** FILE SYSTEM WAS MODIFIED ***** /dev/c/c: 615898/30212096 files (13.6% non-contiguous), 62353456/483393536 blocks After deleting the file (MS Access DB, and re-creating from backup, the file system got mounted read only and the following errors were logged:] May 8 14:58:15 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5124block 167904376:freeing already freed block (bit 1144 May 8 14:58:15 despair kernel: Aborting journal on device dm-0-8. May 8 14:58:15 despair kernel: EXT4-fs (dm-0: Remounting filesystem read-only May 8 14:58:15 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5124block 167904377:freeing already freed block (bit 1145 May 8 14:58:15 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5124block 167904378:freeing already freed block (bit 1146 May 8 14:58:15 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5124block 167904379:freeing already freed block (bit 1147 May 8 14:58:15 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5124block 167904380:freeing already freed block (bit 1148 May 8 14:58:15 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5124block 167904381:freeing already freed block (bit 1149 May 8 14:58:15 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5124block 167904382:freeing already freed block (bit 1150 May 8 14:58:16 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5124block 167904383:freeing already freed block (bit 1151 May 8 14:58:16 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5124block 167904384:freeing already freed block (bit 1152 May 8 14:58:16 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5124block 167904385:freeing already freed block (bit 1153 May 8 14:58:16 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5124block 167904386:freeing already freed block (bit 1154 May 8 14:58:16 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5125block 167949296:freeing already freed block (bit 13296 May 8 14:58:16 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5125block 167949297:freeing already freed block (bit 13297 May 8 14:58:16 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5125block 167949298:freeing already freed block (bit 13298 May 8 14:58:16 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5125block 167949299:freeing already freed block (bit 13299 May 8 14:58:17 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5125block 167949300:freeing already freed block (bit 13300 May 8 14:58:17 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5125block 167949301:freeing already freed block (bit 13301 May 8 14:58:17 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5125block 167949302:freeing already freed block (bit 13302 May 8 14:58:17 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5125block 167949303:freeing already freed block (bit 13303 May 8 14:58:17 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5125block 167949304:freeing already freed block (bit 13304 May 8 14:58:17 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5125block 167949305:freeing already freed block (bit 13305 May 8 14:58:17 despair kernel: EXT4-fs error (device dm-0: mb_free_blocks:1411: group 5125block 167949306:freeing already freed block (bit 13306 These are the same blocks slated as multiply claimed And then running an FSCK, we got the following: ***** File system check forced at Wed May 8 15:16:50 WEST 2013 ***** fsck 1.41.14 (22-Dec-2010 e2fsck 1.42.3 (14-May-2012 /dev/c/c: recovering journal Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information Free blocks count wrong for group #5124 (28170, counted=28159. Fix? yes Free blocks count wrong for group #5125 (25861, counted=25850. Fix? yes Free blocks count wrong (420683133, counted=420644972. Fix? yes Free inodes count wrong (29595347, counted=29595271. Fix? yes /dev/c/c: ***** FILE SYSTEM WAS MODIFIED ***** /dev/c/c: 616825/30212096 files (13.6% non-contiguous, 62748564/483393536 blocks Then later in the year I reloaded the server with the database open from several client machines ***** File system check forced at Tue Jul 23 21:02:13 WEST 2013 ***** fsck 1.42.8 (20-Jun-2013) e2fsck 1.42.8 (20-Jun-2013) Pass 1: Checking inodes, blocks, and sizes Inode 4195619, end of extent exceeds allowed value (logical block 64907, physical block 11435403, len 16) Clear? yes Inode 4195619, i_blocks is 1337216, should be 1337176. Fix? yes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information Block bitmap differences: -(11435403--11435407) Fix? yes Free blocks count wrong for group #348 (2130, counted=2135). Fix? yes Free blocks count wrong (417470107, counted=417470112). Fix? yes /dev/c/c: ***** FILE SYSTEM WAS MODIFIED ***** /dev/c/c: 625785/30212096 files (13.6% non-contiguous), 65923424/483393536 blocks Again related to the same file, which is only an MS Access DB open from several client machines over SMB when the server is rebooted. Moving forward I ensure all instances are closed when reloading but even so I am surprised that a clean reload causes corruption at the filesystem level. Since ensuring the DB is closed before reload, I have seen no further issues like this. Many Thanks Stephen Elliott -----Original Message----- From: Zheng Liu [mailto:gnehzuil.liu@xxxxxxxxx] Sent: 28 October 2013 06:39 To: Andreas Dilger Cc: Stephen Elliott; David Jeffery; linux-ext4@xxxxxxxxxxxxxxx List; Bernd Schubert; Eric Whitney Subject: Re: Query FSCK Errors on ext4 [Cc Eric Whitney to confirm this problem] Hi Andreas, If I remember correctly, this patch might can fix this problem [1]. 1. http://www.spinics.net/lists/linux-ext4/msg39485.html Regards, - Zheng On Mon, Oct 28, 2013 at 12:13:26AM -0600, Andreas Dilger wrote: > The error reported here is a relatively new one. It only appeared in > e2fsck 1.42.8, and wasn t in the code that I m using locally (1.42.7) > so I wasn t sure what it actually meant without looking at it. > > It looks like some kind of overflow of the extent tree, which causes > e2fsck to chop off the last 5 disk blocks (40 sectors), though I m not > sure exactly why. From your comments, this can be reproduced with > your database usage? Does it use fallocate() or any other strange IO > operations that might be causing this? > > Have you tried updating your kernel? If there is repeated corruption > appearing in the filesystem, then it is either a bug in the kernel or > in e2fsck. Not really sure which one to blame at this point. > > Cheers, Andreas > > On Oct 18, 2013, at 9:45 AM, Stephen Elliott <techweb@xxxxxxxxxxxx> wrote: > > > Any feedback on this guys??? Would really appreciate somebody taking a look over this. > > > > From: Stephen Elliott [mailto:techweb@xxxxxxxxxxxx] > > Sent: 22 September 2013 20:13 > > To: linux-ext4@xxxxxxxxxxxxxxx; linux-fsdevel@xxxxxxxxxxxxxxx; Andreas Dilger (adilger@xxxxxxxxx); 'Bernd Schubert' > > Subject: Query FSCK Errors on ext4 > > > > Hi all, > > > > I have theorised that the problem comes from the MS access DB being open (over Samba) on client workstations when the server is reloaded. > > > > Since ensuring these are closed prior to reloading, I have not seen further FSCK errors on reload. Is there an explanation for this? I can see why this may corrupt DB but not the filesystem. > > > > Just as a primer, I used a ReadyNAS NV+ for many years which was running ext3 and never had this issue. However, since using ext4 on a ReadyNAS Pro, I now see this issue. > > > > Many Thanks > > Stephen Elliott > > > > From: Stephen Elliott [mailto:techweb@xxxxxxxxxxxx] > > Sent: 23 July 2013 22:02 > > To: linux-ext4@xxxxxxxxxxxxxxx; linux-fsdevel@xxxxxxxxxxxxxxx; Andreas Dilger (adilger@xxxxxxxxx); 'Bernd Schubert' > > Subject: RE: FSCK Errors on ext4 > > > > If it helps guys, the same file as before is causing the issue with inode 4195610, a very large MS access DB. > > > > From: Stephen Elliott [mailto:techweb@xxxxxxxxxxxx] > > Sent: 23 July 2013 21:52 > > To: linux-ext4@xxxxxxxxxxxxxxx; linux-fsdevel@xxxxxxxxxxxxxxx; Andreas Dilger (adilger@xxxxxxxxx); 'Bernd Schubert' > > Subject: FSCK Errors on ext4 > > > > Hi Andreas / Bernd / all, > > > > You may recall advising me on another batch of FSCK errors a few months back. > > > > The same device on an ext4 file system has produced the following errors after a clean reload. It seems to be fine now but wanted your input on this. No bad blocks are reported on the devices etc. > > > > ***** File system check forced at Tue Jul 23 21:02:13 WEST 2013 ***** fsck 1.42.8 (20-Jun-2013) e2fsck 1.42.8 (20-Jun-2013) Pass 1: Checking inodes, blocks, and sizes Inode 4195619, end of extent exceeds allowed value > > (logical block 64907, physical block 11435403, len > > 16) Clear? yes > > > > Inode 4195619, i_blocks is 1337216, should be 1337176. Fix? yes > > > > Pass 2: Checking directory structure Pass 3: Checking directory > > connectivity Pass 4: Checking reference counts Pass 5: Checking > > group summary information Block bitmap differences: > > -(11435403--11435407) Fix? yes > > > > Free blocks count wrong for group #348 (2130, counted=2135). > > Fix? yes > > > > Free blocks count wrong (417470107, counted=417470112). > > Fix? yes > > > > > > /dev/c/c: ***** FILE SYSTEM WAS MODIFIED ***** > > /dev/c/c: 625785/30212096 files (13.6% non-contiguous), > > 65923424/483393536 blocks > > > > Many Thanks > > Stephen Elliott > > > Cheers, Andreas > > > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" > in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo > info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html