== sanity test 56db: test 'lfs df -m' only shows MDT devices ========================================================== 00:13:35 (1721880815)
UUID                   1K-blocks        Used   Available Use% Mounted on
lustre-MDT0000_UUID      2210560       15616     2192896   1% /mnt/lustre[MDT:0]
lustre-OST0000_UUID      3771392       32768     3736576   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3771392       26624     3742720   1% /mnt/lustre[OST:1]

filesystem_summary:      7542784       59392     7479296   1% /mnt/lustre