== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 20:34:47 (1781224487)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       17388     1253916   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116        9892     1261412   1%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       26936     3580056   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       16664     3590328   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43600     7170384   1%  /mnt/lustre