== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 08:06:54 (1787400414)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       13436     1257868   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       18412     1252892   2%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       23724     3583296   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       19880     3587140   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43604     7170436   1%  /mnt/lustre