== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 02:29:25 (1788848965)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       19184     1252120   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       11708     1259596   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       22720     3584020   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       20860     3586048   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43580     7170068   1% /mnt/lustre