== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 04:57:04 (1787561824)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       11388     1259916   1% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       15848     1255456   2% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       23756     3583264   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       19848     3587172   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43604     7170436   1% /mnt/lustre