Description of problem:
when rebooting after regestering an host, dns configuration is not available anymore

Version-Release number of selected component (if applicable):
latest vdsm and webadmin from the git tree

How reproducible:


Steps to Reproduce:
1.regestering an host which have a functionnal network and dns configuration (DNS1=X.X.X.X) with the webadmin
2.when adding the host is successful, it reboots
3.after rebooting, network config is okay with the ovirtmgmt bridge, but the DNS1 item into the ifcfg-ovirtmgmt file is missing. 
  
Actual results:
impossible to resolve fqdn

Expected results:
resolving sucessfully 

Additional info: