[Lustre-discuss] MDT backup/restore

[Jerome, Ron]

Hi all, 

I attempting to move my MDT to a new server and I'm seeing strange
behavior when trying to restore the MDT tar file taken from the original
disk to the new one.  Basically, the existing MDT data appears to use
about 2.5G, however when I restore the tar file on the new server it
completely fills a 120G partition and the restoration fails with out of
disk space errors??  

I'm a little mystified as to what is happening here since the disk
format is more or less the same, what follows is the disk information
for the original disk followed by the new one.

Any insights would be greatly appreciated...

=============================< Original MDT
>=================================
[root at mds1 data-MDT0000]# df -i
Filesystem            Inodes   IUsed   IFree IUse% Mounted on
/dev/md0             78151680 3368714 74782966    5% /mnt/data


[root at mds1 data-MDT0000]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/md0              112G  2.5G  102G   3% /mnt/data

[root at mds1 data-MDT0000]# tune2fs -l /dev/md0
tune2fs 1.40.11.sun1 (17-June-2008)
device /dev/md0 mounted by lustre per
/proc/fs/lustre/mds/data-MDT0000/mntdev
Filesystem volume name:   data-MDT0000
Last mounted on:          <not available>
Filesystem UUID:          57449444-0de9-42e3-a919-70d216bc01f5
Filesystem magic number:  0xEF53
Filesystem revision #:    1 (dynamic)
Filesystem features:      has_journal ext_attr resize_inode dir_index
filetype needs_recovery sparse_super large_file
Filesystem flags:         signed_directory_hash
Default mount options:    (none)
Filesystem state:         clean
Errors behavior:          Continue
Filesystem OS type:       Linux
Inode count:              78151680
Block count:              39070048
Reserved block count:     1953502
Free blocks:              28643263
Free inodes:              74782966
First block:              0
Block size:               4096
Fragment size:            4096
Reserved GDT blocks:      1024
Blocks per group:         16384
Fragments per group:      16384
Inodes per group:         32768
Inode blocks per group:   4096
Filesystem created:       Tue May 29 13:49:47 2007
Last mount time:          Thu May 21 13:18:25 2009
Last write time:          Thu May 21 13:18:25 2009
Mount count:              180
Maximum mount count:      22
Last checked:             Tue May 29 13:49:47 2007
Check interval:           15552000 (6 months)
Next check after:         Sun Nov 25 12:49:47 2007
Reserved blocks uid:      0 (user root)
Reserved blocks gid:      0 (group root)
First inode:              11
Inode size:               512
Journal inode:            8
Default directory hash:   tea
Directory Hash Seed:      cf133553-2ae6-42a1-b0b5-cfbad6fd104b
Journal backup:           inode blocks

=============================< New MDT
>=================================

[root at mds2 ~]# df -i
Filesystem            Inodes   IUsed   IFree IUse% Mounted on
/dev/md2             35848192  384427 35463765    2% /root/data

[root at mds2 ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/md2              120G  120G     0 100% /root/data

[root at mds2 ~]# tune2fs -l /dev/md2
tune2fs 1.40.11.sun1 (17-June-2008)
Filesystem volume name:   data-MDT0000
Last mounted on:          <not available>
Filesystem UUID:          d197b003-5ce5-4d1b-8253-b196b2009d07
Filesystem magic number:  0xEF53
Filesystem revision #:    1 (dynamic)
Filesystem features:      has_journal ext_attr resize_inode dir_index
filetype needs_recovery sparse_super large_file uninit_groups
Filesystem flags:         signed_directory_hash
Default mount options:    (none)
Filesystem state:         clean
Errors behavior:          Continue
Filesystem OS type:       Linux
Inode count:              35848192
Block count:              35842992
Reserved block count:     1792149
Free blocks:              125970
Free inodes:              35463765
First block:              0
Block size:               4096
Fragment size:            4096
Reserved GDT blocks:      1015
Blocks per group:         32768
Fragments per group:      32768
Inodes per group:         32768
Inode blocks per group:   4096
Filesystem created:       Wed May 20 16:45:54 2009
Last mount time:          Thu May 21 13:27:52 2009
Last write time:          Thu May 21 13:27:52 2009
Mount count:              14
Maximum mount count:      26
Last checked:             Wed May 20 16:45:54 2009
Check interval:           15552000 (6 months)
Next check after:         Mon Nov 16 15:45:54 2009
Reserved blocks uid:      0 (user root)
Reserved blocks gid:      0 (group root)
First inode:              11
Inode size:               512
Journal inode:            8
Default directory hash:   tea
Directory Hash Seed:      819ff3d7-b341-4300-8cd8-b6a6b3020c4e
Journal backup:           inode blocks
_________________________________________
Ron Jerome
Programmer/Analyst
National Research Council Canada
M-2, 1200 Montreal Road, Ottawa, Ontario K1A 0R6
Government of Canada
Phone: 613-993-5346
FAX:   613-941-1571
_________________________________________