== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 12:53:32 (1788368012)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       17096     1254208   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       20820     1250484   2%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       23420     3583600   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       21152     3585868   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       44572     7169468   1%  /mnt/lustre