I have a new box with Ensim 10.3.0

I have changed the hostname and I am able to add new sites as long as there are no slave Name servers.

When I add a secondary NS or a virtual Name server. I cannot edit the default site plan, or add or edit an existing site.
When a slave is present I get the following error:
hostname does not resolve.

I have several other boxes and have never encountered this particular error. I cannot find the problem.

Any help would be appreciated