== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 19:29:22 (1784417362)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       19884     1251420   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       13716     1257588   2%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       23128     3583892   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       21448     3585572   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       44576     7169464   1%  /mnt/lustre