== sanity test 56db: test 'lfs df -m' only shows MDT devices ========================================================== 00:33:14 (1764739994)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       17900     1253404   2%  /mnt/lustre[MDT:0]
lustre-MDT0001_UUID      1414116       25540     1245764   3%  /mnt/lustre[MDT:1]
lustre-OST0000_UUID      3833116       27084     3579936   1%  /mnt/lustre[OST:0]
lustre-OST0001_UUID      3833116       18512     3588508   1%  /mnt/lustre[OST:1]

filesystem_summary:      7666232       45596     7168444   1%  /mnt/lustre