== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 22:31:12 (1787106672)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       21608     1249696   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       16120     1255184   2%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       30880     3576140   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       14776     3592244   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       45656     7168384   1%  /mnt/lustre