== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 12:56:18 (1788540978)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       11732     1259572   1% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       16696     1254608   2% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       28828     3577772   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       14828     3592080   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43656     7169852   1% /mnt/lustre