== sanity test 56db: test 'lfs df -m' only shows MDT devices ========================================================== 06:40:31 (1744540831)
UUID                   1K-blocks        Used   Available Use% Mounted on
lustre-MDT0000_UUID      1414116       17956     1269732   2% /mnt/lustre[MDT:0]
lustre-MDT0001_UUID      1414116       24572     1263116   2% /mnt/lustre[MDT:1]
lustre-OST0000_UUID      3833116       31256     3575764   1% /mnt/lustre[OST:0]
lustre-OST0001_UUID      3833116       12876     3594144   1% /mnt/lustre[OST:1]

filesystem_summary:      7666232       44132     7169908   1% /mnt/lustre