== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 23:46:27 (1789616787)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      2209792       12288     2195456   1% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      2210048       10368     2197632   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3771392       31744     3737600   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3771392       18432     3750912   1% /mnt/lustre[OST:1] 

filesystem_summary:      7542784       50176     7488512   1% /mnt/lustre