Nortel Contact Center Multimedia Installation And Maintenance Manual page 1546

Change the names or IP addresses of servers
If you do not see a server name for the Contact Center Manager Server
listed in the HOSTS file, a DNS server is configured in your network for
name resolution. You do not need to update the HOSTS file.
4 Click File > Save to save your changes.
Save the file without an extension so that your system recognizes the
changes.
Result: The system automatically reads the new settings.
5 Close all windows to complete the procedure.
1546 Contact Center Multimedia/Outbound
Standard 7.16