Increasing Thumper filesystems for DPM

The file systems on Thumper disk servers can be grown on demand. Here follows the recipe to increase the file systems.

If the XFS file system should grow by more than 2 TB, see section Increasing file systems by more than 2 TB for more details.

Increase the logical volume (/dev/data/atlasprd) on the Thumper. In this example, increase it 4.4 TB (SI):

[root@hooi-ei-01 ~]# lvresize -L 4T /dev/data/atlasprd
  Extending logical volume atlasprd to 4.00 TB
  Logical volume atlasprd successfully resized

Increase the size of the XFS file system:

[root@hooi-ei-01 ~]# xfs_growfs /export/data/lv0
meta-data=/dev/data/atlasprd     isize=256    agcount=32, agsize=16777216 blks
         =                       sectsz=512   attr=0
data     =                       bsize=4096   blocks=536870912, imaxpct=25
         =                       sunit=0      swidth=0 blks, unwritten=1
naming   =version 2              bsize=4096
log      =internal               bsize=4096   blocks=32768, version=1
         =                       sectsz=512   sunit=0 blks, lazy-count=0
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 536870912 to 1073741824

The system should now see the modified size of the file system:

[root@hooi-ei-01 ~]# df -hH | grep -A 1 atlasprd
/dev/mapper/data-atlasprd
                       4.4T   1.6T   2.9T  37% /export/data/lv0

The DPM server has to be restarted to make it aware of this extra disk space:

[root@tbn18 ~]# service dpm restart
Stopping dpm:                                              [  OK  ]
Starting dpm:                                     

Done!

Increasing file systems by more than 2 TB

there seems to be an integer overflow in the xfs_grow command, which limits the increase of the file system to 2 TB (the exact maximum was not determined; however, increasing in steps of 2 TB was fine, going from 2 to 12 in one go was not).