== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 01:41:05 (1788932465)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       16380     1254924   2% /mnt/lustre[MDT:0] 
lustre-OST0000_UUID      3833116       20636     3586384   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       22368     3584652   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43004     7171036   1% /mnt/lustre