== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 08:54:39 (1779108879)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       17608     1253696   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       10280     1261024   1%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       23804     3583216   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       19768     3587000   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43572     7170216   1%  /mnt/lustre