Steps to reproduce:

1. Specify the proxy address as ServerActive
2. Specify the HostInterface or HostInterfaceItem
3. Create the autoregistration action
4. Restart the agent

Result:
Agent will not be registered. Server reports an error in the log:

process_autoregistration_contents(): "" is not a valid IP address

With the server itself it's working fine

Expected:
Registered host with the DNS address specified in the HostInterface