== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 03:36:01 (1790753761)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       11208     1260096   1% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       16020     1255284   2% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       26804     3580216   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       16748     3590272   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43552     7170488   1% /mnt/lustre