== sanity test 56db: test 'lfs df -m' only shows MDT devices ========================================================== 02:30:20 (1746167420)
UUID                   1K-blocks        Used   Available Use% Mounted on
lustre-MDT0000_UUID      1414116       15780     1271908   2% /mnt/lustre[MDT:0]
lustre-MDT0001_UUID      1414116       21312     1266376   2% /mnt/lustre[MDT:1]
lustre-OST0000_UUID      3833116       31008     3576012   1% /mnt/lustre[OST:0]
lustre-OST0001_UUID      3833116       12140     3594880   1% /mnt/lustre[OST:1]

filesystem_summary:      7666232       43148     7170892   1% /mnt/lustre