== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 05:02:28 (1789030948)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       17480     1253824   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116        9848     1261456   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       28212     3578724   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       15392     3591544   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43604     7170268   1% /mnt/lustre