== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 22:02:27 (1787104947)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       21372     1249932   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       15804     1255500   2%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       31244     3575776   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       14380     3592640   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       45624     7168416   1%  /mnt/lustre