== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 15:00:22 (1788548422)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       19232     1252072   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       11800     1259504   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       21792     3585228   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       21764     3585256   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43556     7170484   1% /mnt/lustre