== sanity test 56db: test 'lfs df -m' only shows MDT devices ========================================================== 05:51:38 (1734432698)
UUID                   1K-blocks        Used   Available Use% Mounted on
lustre-MDT0000_UUID      2210432       13824     2194560   1% /mnt/lustre[MDT:0]
lustre-OST0000_UUID      3771392       25600     3743744   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3771392       28672     3740672   1% /mnt/lustre[OST:1]

filesystem_summary:      7542784       54272     7484416   1% /mnt/lustre