== sanity test 56db: test 'lfs df -m' only shows MDT devices ========================================================== 01:58:00 (1746165480)
UUID                   1K-blocks        Used   Available Use% Mounted on
lustre-MDT0000_UUID      1414116       15892     1271796   2% /mnt/lustre[MDT:0]
lustre-MDT0001_UUID      1414116       21336     1266352   2% /mnt/lustre[MDT:1]
lustre-OST0000_UUID      3833116       26600     3580420   1% /mnt/lustre[OST:0]
lustre-OST0001_UUID      3833116       16548     3590472   1% /mnt/lustre[OST:1]

filesystem_summary:      7666232       43148     7170892   1% /mnt/lustre