== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 02:10:40 (1789279840)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       17316     1253988   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116        9752     1261552   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       30132     3576860   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       13468     3593440   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43600     7170300   1% /mnt/lustre