== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 14:44:34 (1787856274)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       11080     1260224   1%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       15980     1255324   2%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       31892     3574988   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       11716     3595052   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43608     7170040   1%  /mnt/lustre