== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 22:34:52 (1781231692)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       12328     1258976   1%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       16748     1254556   2%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       22984     3584036   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       20616     3586404   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43600     7170440   1%  /mnt/lustre