Terminal Server Pros and Cons Page 3
Here is a breakdown of the main cons of Microsoft Terminal Services for Windows 2000.
Because everything runs off of the Terminal Server there is more requirements for hardware. In my experience the average user (Outlook Email, IBM Client Access Express, and the occasional Internet Explorer session or Word) requires between 10 and 20 MB of Ram. Also Windows 2000 with Terminal Services running takes between 120 - 200MB just to run. My server has ~780MB of Ram and is currently servicing 15 Clients with more being added everyday. I expect to encounter memory problems when we have about 50 Clients accessing the server regularly and then I'll just add some more memory.
The other major requirement is processor power. My server is running Dual Pentium II-400 and with our current load we are sitting around 15% utilization consistently. This value was created by Performance monitor logging over a 24hr period.
If you keep a regular check on the Performance Monitor logs you can be prepared for the increased load that Terminal Server will cause.
Some Programs don't work properly
What I find to be the biggest pain of running Terminal Server is that some programs don't work properly and some don't work at all. The main one I've encountered is Microsoft Photo Editor that comes with Office 2000 doesn't run under terminal server.
Even when programs do run there may be compatibility scripts that must be used when installing to make sure that they do in fact perform properly.
The biggest thing I can say about this is test and make sure your important software either works under terminal server or can be replaced with a program that works under terminal server.
Server Security needs to be strong
This one is fairly self explanatory. Because your users are logging onto your server directly you need to either trust them explicitly not to go playing around or you need to lock down the important areas to prevent them from playing around. Since I don't really trust my users (been called out to many times to fix PC's because they do play around) I implemented policies to prevent them from accessing the boot partition, control panel and everything else they didn't need to access. I also redirected their start menu, desktop and my documents to their personal directories.
The main thing to say here is test your installation on a spare box before implementation and backup the server first just in case something goes wrong. Once you have installed the service on your server install the programs needed and test your setup on yourself before setting up the final users.
You are going to need to set up your default profile to only display the programs the users need and get rid of everything else. It also helps to log on as some of the users to make sure the profile changes work. I also implemented a common start menu that everyone uses and that is only stored in one location so changes are only made to one place.
Microsoft Licensing Model
This has to be the worst part of the whole setup. You have to buy licenses for terminal services, then register them online with Microsoft, and finally they are per machine licenses that will go with the machine should it fail or be rebuilt. The only way to recover these licenses involves contacting Microsoft and getting your license reset which, I've heard, is not that easy to do.
The other licensing option is to get a Microsoft Enterprise License Agreement and then you can run as many Terminal Services as you want. It also gives you license to a bunch of other Microsoft Desktop Software, but you agree to pay a set amount of money per desktop for a 3 year period.