Summary
There is a function that you can use to provide a local client IP address to an application on Presentation Server by adding the registry entry, UseClientIP. This function is used for identification purposes by some applications that use the gethostbyname type function which is provided by Winsock.
Remark: UseClientIP does NOT assign a client IP address as a Virtual IP address. Such a published application actually uses a Server IP address as its own IP to communicate with an external application.
For example: When launching Internet Explorer as a published application with UseClientIP registry configured, Internet Explorer itself uses a Server IP address to connect to some Web site (Web Server).
How to Provide Client IP addresses to applications
Instructions for how to provide Client IP addresses to published applications can be found in CTX106319 - MetaFrame Presentation Server 4.0 Administrator's Guide(P.249 “Providing the Client IP Address to an Application”) is as follows;
To supply client IP addresses to published applications on a server
1. On the server on which the applications reside, start regedit.
CAUTION Using Registry Editor incorrectly can cause serious problems that can require you to reinstall the operating system. Citrix cannot guarantee that problems resulting from incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk. Make sure you back up the registry before you edit it.
2. Using regedit, create the following two registry entries:
HKEY_LOCAL_MACHINE\Software\Citrix\VIP\
Name: UseClientIP
Type: REG_DWORD
Data: 1 (enable) or 0 (disable, which is the default)
HKEY_LOCAL_MACHINE\Software\Citrix\VIP\
Name: HookProcessesClientIP
Type: REG_MULTI_SZ
Data: multiple executable names representing application processes that use client IP addresses
3. Close regedit and restart your server.
4. After making the prescribed registry modifications, in the Presentation Server Console, use the farm properties page, Virtual IP Processes, to add the application process. For instructions, see “Enabling Applications for Use with Virtual IP Addresses or Virtual Loopback Address” on page 252.
How to confirm the functionality
UseClientIP doesn’t give any virtually assigned IP address to the session at glace. So you can not tell if the UseClientIP registry modification actually works from the session information on Presentation Management Console or some other ways (such as the netstat command within the session) unless a published application in the session shows the related information for it.
To confirm it, download NetAppWin.zip and publish it from Presentation Server with the registry modification for UseClientIP. Once you launch NetAppWin.exe as a published application, you will see your client local IP address assigned in the “IP address” field.
This “IP address” is taken from the gethostbyname function from Winsock. Some applications use a gethostbyname type function to get an IP address for identification purpose. If you have such applications on Presentation Server, you can use UseClientIP for the application to work properly.
