== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 23:35:26 (1781235326)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       13144     1258160   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       18172     1253132   2%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       20724     3586296   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       22876     3584144   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43600     7170440   1%  /mnt/lustre