== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 14:10:41 (1785089441)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       16940     1254364   2%  /mnt/lustre[MDT:0] 
lustre-OST0000_UUID      3833116       21660     3585360   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       21392     3585628   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43052     7170988   1%  /mnt/lustre