== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 03:38:07 (1788593887)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       17348     1253956   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116        9828     1261476   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       27780     3579240   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       15824     3591196   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43604     7170436   1% /mnt/lustre