== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 01:14:51 (1790745291)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       17656     1253648   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       10252     1261052   1% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       28176     3578844   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       15380     3591640   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       43556     7170484   1% /mnt/lustre