== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 17:08:53 (1789592933)
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       30720     3729408   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3771392       19456     3734528   1% /mnt/lustre[OST:1] 

filesystem_summary:      7542784       50176     7463936   1% /mnt/lustre