== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 12:47:20 (1790959640)
UUID                   1K-blocks        Used   Available Use% Mounted on 
lustre-MDT0000_UUID      1414116       17260     1254044   2% /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       20264     1251040   2% /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       21676     3585344   1% /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       23936     3583084   1% /mnt/lustre[OST:1] 

filesystem_summary:      7666232       45612     7168428   1% /mnt/lustre