== sanity test 56db: test 'lfs df -m' only shows MDT devices ========================================================== 06:20:26 (1768562426)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       14268     1257036   2%  /mnt/lustre[MDT:0]
lustre-MDT0001_UUID      1414116       19568     1251736   2%  /mnt/lustre[MDT:1]
lustre-OST0000_UUID      3833116       26952     3580068   1%  /mnt/lustre[OST:0]
lustre-OST0001_UUID      3833116       16600     3590420   1%  /mnt/lustre[OST:1]

filesystem_summary:      7666232       43552     7170488   1%  /mnt/lustre