== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 23:16:17 (1789614977)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       19316     1251988   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       11896     1259408   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       20680     3586228   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       22892     3583792   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43572     7170020   1% /mnt/lustre