== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 15:13:45 (1788462825)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       11352     1259952   1% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       16312     1254992   2% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       21824     3584748   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       21784     3585096   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43608     7169844   1% /mnt/lustre