== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 03:15:53 (1790666153)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      2209792       10368     2197376   1% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      2210048        8448     2199552   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3771392       25600     3743744   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3771392       24576     3724288   1% /mnt/lustre[OST:1] 

filesystem_summary:      7542784       50176     7468032   1% /mnt/lustre