== sanity test 56Db: test 'lfs df -m' only shows MDT devices ========================================================== 02:05:12 (1783145112)
UUID                   1K-blocks        Used   Available Use%  Mounted on
lustre-MDT0000_UUID      1414116       13484     1257820   2%  /mnt/lustre[MDT:0] 
lustre-MDT0001_UUID      1414116       17324     1253980   2%  /mnt/lustre[MDT:1] 
lustre-OST0000_UUID      3833116       25508     3581512   1%  /mnt/lustre[OST:0] 
lustre-OST0001_UUID      3833116       19064     3587956   1%  /mnt/lustre[OST:1] 

filesystem_summary:      7666232       44572     7169468   1%  /mnt/lustre