== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 15:23:00 (1788808980)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       18256     1253048   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       11160     1260144   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       27812     3579208   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       15744     3591276   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43556     7170484   1% /mnt/lustre