== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 10:17:42 (1788272262)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       11812     1259492   1% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       16532     1254772   2% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       28960     3578060   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       14596     3592424   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43556     7170484   1% /mnt/lustre