I have 9 partitions formatted as XFS on my server.
When I try to mount one of them, it fails. The others mount fine.
root@fileserver2 # mount | grep xfs | head -1
/dev/sdb1 on /mnt/hdd1 type xfs (rw,noatime)
root@fileserver2 # mount -t xfs /dev/sdf3 /mnt/hdd3
mount: wrong fs type, bad option, bad superblock on /dev/sdf3,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so
root@fileserver2 # dmesg | tail -2
XFS (sdf3): bad magic number
XFS (sdf3): SB validate failed
So I tried to use xfs_repair -n to find secondary SB, but that failed:
root@fileserver2 # xfs_check /dev/sdf3
xfs_check: /dev/sdf3 is not a valid XFS filesystem (unexpected SB magic number 0x00000000)
xfs_check: WARNING - filesystem uses v1 dirs,limited functionality provided.
xfs_check: read failed: Invalid argument
xfs_check: data size check failed
cache_node_purge: refcount was 1, not zero (node=0x14a7380)
xfs_check: cannot read root inode (22)
bad superblock magic number 0, giving up
root@fileserver2 # xfs_repair -n /dev/sdf3
Phase 1 - find and verify superblock...
bad primary superblock - bad magic number !!!
attempting to find secondary superblock...
............[etc.]
...found candidate secondary superblock... unable to verify superblock, continuing...
[etc.]
...Sorry, could not find valid secondary superblock
Exiting now.
Here's the partitions on that specific drive, which include the root partition (sdf1), and the swap partition (sdf5). I find it weird that the Extended partition doesn't included my sdf3 (XFS) partition. That would mean my XFS partition would be a second primary partition, right?
root@fileserver2 # fdisk -l /dev/sdf
Disk /dev/sdf: 2000.4 GB, 2000398934016 bytes
255 heads, 63 sectors/track, 243201 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x20a0c72d
Device Boot Start End Blocks Id System
/dev/sdf1 * 1 2612 20980858+ 83 Linux
/dev/sdf2 2613 2855 1951867 5 Extended
/dev/sdf3 2856 243202 1930581796+ 83 Linux
/dev/sdf5 2613 2855 1951866 82 Linux swap / Solaris
Next, I tried to use file -s
to identify the various file-systems on that drive:
root@fileserver2 # file -s /dev/sdf1
/dev/sdf1: Linux rev 1.0 ext4 filesystem data (needs journal recovery) (extents) (large files) (huge files)
root@fileserver2 # file -s /dev/sdf2
/dev/sdf2: x86 boot sector; partition 1: ID=0x82, starthead 254, startsector 2, 3903732 sectors, extended partition table (last)\011, code offset 0x1
root@fileserver2 # file -s /dev/sdf3
/dev/sdf3: x86 boot sector; partition 1: ID=0xbf, starthead 254, startsector 63, 3861163530 sectors, extended partition table (last)\011, code offset 0x0
root@fileserver2 # file -s /dev/sdf5
/dev/sdf5: Linux/i386 swap file (new style) 1 (4K pages) size 487965 pages
So, sdf3 appears to be a second extended partition..? Weird.
I tried the same command on a XFS partition that I can mount:
root@fileserver2 # file -s /dev/sdb1
/dev/sdb1: SGI XFS filesystem data (blksz 4096, inosz 256, v2 dirs)
And also tried to check the data at the beginning of the sdf3 partition:
root@fileserver2 # dd if=/dev/sdf3 bs=512 count=64 iflag=direct | hexdump -C
00000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
000001b0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fe |................|
000001c0 ff ff bf fe ff ff 3f 00 00 00 0a ae 24 e6 00 00 |......?.....$...|
000001d0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
000001f0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 55 aa |..............U.|
00000200 9c 52 1d 9c b7 00 d7 e9 e8 fc 3c 6f 4e dc 31 27 |.R........<oN.1'|
00000210 e9 98 6b b0 2f 74 c1 69 40 12 58 90 4b e3 d0 73 |..k./t.i@.X.K..s|
[...]
00007e00 58 46 53 42 00 00 10 00 00 00 00 00 1c c4 95 c1 |XFSB............|
00007e10 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
00007e20 41 4c 30 10 33 23 45 5f 88 6c 25 e1 03 a1 be e3 |AL0.3#E_.l%.....|
00007e30 00 00 00 00 10 00 00 04 00 00 00 00 00 00 00 80 |................|
00007e40 00 00 00 00 00 00 00 81 00 00 00 00 00 00 00 82 |................|
00007e50 00 00 00 01 07 31 25 71 00 00 00 04 00 00 00 00 |.....1%q........|
00007e60 00 03 98 92 b4 a4 02 00 01 00 00 10 68 64 64 33 |............hdd3|
00007e70 00 00 00 00 00 00 00 00 0c 09 08 04 1b 00 00 05 |................|
00007e80 00 00 00 00 00 00 00 40 00 00 00 00 00 00 00 3d |.......@.......=|
00007e90 00 00 00 00 1c c0 fd 1b 00 00 00 00 00 00 00 00 |................|
00007ea0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
00007eb0 00 00 00 00 00 00 00 02 00 00 00 00 00 00 00 00 |................|
00007ec0 00 00 00 00 00 00 00 01 00 00 00 0a 00 00 00 0a |................|
00007ed0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
00008000
(Full dump of result: http://f.cl.ly/items/3I3F3c1F1I1Z2f1w1W3Z/hexdump-sdf3.txt)
So, instead of having the partition start on sector 0 (like they do on other drives, like sdb1), it starts at sector 63 (0x7e00 = 32256 / 512 bytes/sector = 63).
Any pointer on how I could resolve that problem, and be able to mount this funny partition?
Thanks.