== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 04:54:10 (1788944050)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       17216     1254088   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116        9652     1261652   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       20784     3586124   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       22808     3583792   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43592     7169916   1% /mnt/lustre