== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 08:44:59 (1781613899)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       17980     1253324   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       10652     1260652   1%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       28020     3579000   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       15524     3591496   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43544     7170496   1%  /mnt/lustre