== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 12:35:55 (1790958955)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       17572     1253732   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       10136     1261168   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       24628     3582392   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       18924     3588096   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43552     7170488   1% /mnt/lustre