== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 06:26:11 (1787826371)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      2210176        8448     2199680   1% /mnt/lustre[MDT:0] 
lustre-OST0000_UUID      3771392       22528     3746816   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3771392       25600     3743744   1% /mnt/lustre[OST:1] 

filesystem_summary:      7542784       48128     7490560   1% /mnt/lustre