== sanity test 56db: test 'lfs df -m' only shows MDT devices ========================================================== 00:12:40 (1746159160)
UUID                   1K-blocks        Used   Available Use% Mounted on
lustre-MDT0000_UUID      2210432       13952     2194432   1% /mnt/lustre[MDT:0]
lustre-OST0000_UUID      3771392       23552     3745792   1% /mnt/lustre[OST:0]
lustre-OST0001_UUID      3771392       23552     3745792   1% /mnt/lustre[OST:1]

filesystem_summary:      7542784       47104     7491584   1% /mnt/lustre