== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 11:11:20 (1790953880)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       19428     1251876   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       11900     1259404   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       31884     3575136   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       11672     3595348   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43556     7170484   1% /mnt/lustre