== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 15:28:09 (1785785289)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       19180     1252124   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       11792     1259512   1%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       22052     3584968   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       21552     3585468   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43604     7170436   1%  /mnt/lustre