== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 01:18:00 (1789190280)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       20932     1250372   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       15388     1255916   2% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       23396     3583540   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       21860     3585160   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       45256     7168700   1% /mnt/lustre