== sanity test 56db: test 'lfs df -m' only shows MDT devices ========================================================== 01:52:47 (1763880767)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       16768     1254536   2%  /mnt/lustre[MDT:0]
lustre-MDT0001_UUID      1414116       23508     1247796   2%  /mnt/lustre[MDT:1]
lustre-OST0000_UUID      3833116       30496     3576524   1%  /mnt/lustre[OST:0]
lustre-OST0001_UUID      3833116       14072     3592948   1%  /mnt/lustre[OST:1]

filesystem_summary:      7666232       44568     7169472   1%  /mnt/lustre