== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 17:59:37 (1788299977)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       11216     1260088   1%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       16104     1255200   2%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       28760     3578008   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       14824     3592196   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43584     7170204   1%  /mnt/lustre