== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 12:02:42 (1787328162)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       19240     1252064   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       11756     1259548   1%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       20544     3586364   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       23044     3583892   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43588     7170256   1%  /mnt/lustre