What do you mean the “host file”? (Pardon my ignorance.) Where would that be?
Windows:
.
Add the primary server to the hosts file of the Windows client computer:
Use a text editor to open C:\Windows\system32\drivers\etc\HOSTS .
Add a line that identifies the server's IP address and name, in this format:
<IP address><host name>
where <IP address> is the IP address of the server
where <host name> is the DNS name of the server
Save and close the file.
Do not accidentally add a file name extension, such as .txt .
Mac:
Add the primary server to the hosts file of the Mac client computer:
Log on to the Mac client computer with an administrator account.
In Finder, click Go > Utilities.
Double-click Terminal.
In the Terminal dialog box, type sudo nano /etc/hosts
If you are prompted for a password, type your password.
Add the IP address of the Prinergy primary server in the following format:
ip hostname
Press Ctrl+X, press Y to save your changes, and press Enter to save the file in the /etc folder.