== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 21:02:43 (1788656563)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       19460     1251844   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       11600     1259704   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       25808     3581212   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       17800     3589220   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43608     7170432   1% /mnt/lustre