== sanity test 56db: test 'lfs df -m' only shows MDT devices ========================================================== 17:16:10 (1741900570)
UUID                   1K-blocks        Used   Available Use% Mounted on
lustre-MDT0000_UUID      2210432       24832     2183552   2% /mnt/lustre[MDT:0]
lustre-OST0000_UUID      3771392       28672     3740672   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3771392       27648     3741696   1% /mnt/lustre[OST:1]

filesystem_summary:      7542784       56320     7482368   1% /mnt/lustre