== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 01:31:02 (1787895062)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       17760     1253544   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       10224     1261080   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       27052     3579856   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       16532     3590152   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43584     7170008   1% /mnt/lustre