== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 13:00:54 (1786381254)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       18032     1253272   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       10372     1260932   1%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       28948     3577652   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       14604     3592248   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43552     7169900   1%  /mnt/lustre