== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 04:45:44 (1788857144)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       11272     1260032   1% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       16208     1255096   2% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       22740     3584280   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       20868     3586152   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43608     7170432   1% /mnt/lustre