Description of problem:

Lets assume it takes the configuration as below.

eth0:
eth1: primary + provisioning named test.example.com

We attempt to change eth0 to the primary interface because eth1 is actually on a private network we get a validation error of "Some of the interfaces are invalid. Please check the table below." and eth0 is highlighted. When we Edit eth0 it says the DNS name is already taken. If we attempt the operation again by removing the DNS name and domain from eth1 the validation still fails for the same reason. The only way I've been able to modify a host's primary interface has been by giving the new primary interface a completely new name. This results in the host having a new, incorrect, FQDN then we have to go back and change back to the original hostname.

Version-Release number of selected component (if applicable):

How reproducible:

Steps to Reproduce:

1. Create a host with 2 NICs
2. Change the primary interface flag from eth1 to eth0

Actual results:

Failed with DNS name is already taken

Expected results:

We should be able to change the interface without any issue.

Additional info:

Workaround:

Modify a host's primary interface new primary interface with a completely new name (test.example.com to test-temp.example.com). This results in the host having a new, incorrect, FQDN then we have to go back and change back to the original hostname (test-temp.example.com to test.example.com).