== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 21:52:09 (1787881929)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       11300     1260004   1%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       15976     1255328   2%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       24684     3582336   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       18924     3588096   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43608     7170432   1%  /mnt/lustre