If an external application is not connecting with an application on a DeltaV workstation you may need to modify the Windows Hosts file. Some applications require the use of a Windows Hosts file to resolve a host name to an IP address in order to communicate with internal workstations through the firewall. Name resolution cannot be configured on the firewall; it must be configured on some or all of the external workstations.
We recommend that you create a Hosts file for each workstation that will communicate through the firewall. This is a simple text file that is used to associate a computer name with a network IP address. Some applications use computer names rather than network IP addresses to access computers and the Hosts file is needed to provide the name for network address resolution.