== sanity test 56db: test 'lfs df -m' only shows MDT devices ========================================================== 12:37:31 (1776875851)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       18168     1253136   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       25204     1246100   2%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       21556     3585464   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       24080     3582940   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       45636     7168404   1%  /mnt/lustre