== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 01:23:22 (1789277002)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       10856     1260448   1% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       15828     1255476   2% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       30836     3575820   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       12740     3594196   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43576     7170016   1% /mnt/lustre