== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 00:19:38 (1788754778)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       18468     1252836   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       11544     1259760   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       32124     3574896   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       11424     3595596   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43548     7170492   1% /mnt/lustre