== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 00:27:44 (1788841664)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      2210048        8192     2199808   1% /mnt/lustre[MDT:0] 
lustre-OST0000_UUID      3771392       23552     3723264   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3771392       24576     3744768   1% /mnt/lustre[OST:1] 

filesystem_summary:      7542784       48128     7468032   1% /mnt/lustre