Christa Anderson, an internationally known speaker, writer and authority on server-based computing, has joined SearchWin2000.com as an expert to answer your terminal services questions. In this article, Christa fields questions on everything from testing to connecting through a VPN.
SearchWin2000.com member: What testing do I have to do for an application that is installed on a terminal server? Or, can you give me the checkpoints that I have to go through to make sure the application maintains its integrity on a terminal server?
Anderson: I'm not sure what you mean by application integrity; applications aren't liable to corruption on a terminal server any more than they are anywhere else. When testing applications for suitability on a terminal server, here's a quick checklist of the kinds of things you're looking for:
- Applications that identify users by name, not by machine name or machine IP address.
- Applications that don't overtax system resources such as processor time or memory. Memory leaks or constant CPU polling are very bad in an application running on a shared system.
- On Win2k, terminal services without MetaFrame, applications that work well with a maximum color depth of 256 colors.
- Thirty-two bit applications, rather than 16-bit applications. All else being equal -- and it usually isn't -- 32-bit applications will use less memory than 16-bit applications, because 16-bit applications must all run within a private virtual machine that does not allow them to share code.
SearchWin2000.com member: I have a problem connecting to my terminal server through a VPN. I currently have a DSL line at home and can create a tunnel to my work network through our Cisco router, but when I try to connect to our terminal server with a terminal services client, it times out. I have tried various ways to solve this problem but have been unsuccessful.
Anderson: You don't elaborate on the solutions you've already tried, but my first guess is that port 3389 (used for RDP traffic) is not open.
SearchWin2000.com member: I am planning a Win2k network from scratch. I have two locations connected by a dedicated T1 and used by a total of 50 users -- 30 of which are in the building that will house the server. I am planning on using terminal services to host the core dealer management software, Office (to selected users) and possibly DVD-ROM-based service manuals to the repair shop. All the clients are either Win9x or Win2k.
The budget is a bit tight, so I am wondering if I can get away with having the server as a domain controller as well as a terminal server. All the logons occur in the morning. Once everyone is on, they stay on, so I expect a performance hit in the morning. Am I going about this the proper way, or should I suck it up and get another box for a DC?
Anderson: You can make a domain controller a terminal server if you edit user permissions to allow them to log on interactively with a domain controller. (Otherwise, only administrators will be able to log on.) However, I don't recommend doing so. A domain controller is not just active at user logon, and the double duty of authenticating users and supporting 50 users running applications will put a big strain on the computer -- and hurt performance in both directions. Also, I'm not crazy about putting users on a domain controller. If the terminal server crashes due to a buggy driver or some other user-environment problem, you've lost your domain controller.
SearchWin2000.com member: I have a Win2k server PC and five client workstations (three are local and two run terminal services). All workstations (local and TS) can run a DOS app with no problem. Recently, I had a client/server app installed on the server by a developer. The app runs fine on a local client, but a terminal services client gets the following message: 'Component "MSDATGRD.OCX" or one of its dependencies not correctly registered: a file is missing or invalid.'
If I run the app locally on the client workstation, it works OK, but it fails with the above message if I try to run it under terminal services on the same machine. All clients are running Win98. I even upgraded one of the PCs to run Win2k Pro, but the same circumstances occur. It sounds like terminal services is missing some privilege settings on the server. Help, please!
Anderson: This is an application problem, not a terminal server problem per se. I recommend that you have the developer check out the document here to see if the application is organized properly for running on a multi-user computer.
This was first published in June 2003