== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 10:39:30 (1783521570)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       23572     1247732   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       18048     1253256   2%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       30908     3576112   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       14732     3592288   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       45640     7168400   1%  /mnt/lustre