Server Hardware Sizing
You must consider many factors when sizing your MetaFrame server, but you should start with the basics. Make sure you fulfill the operating system requirements based on vendor recommendations as follows:
- Windows 2000 Server and Advanced Server—Microsoft’s minimum recommended hardware for these operating systems includes a 166MHz Pentium with 256MB RAM and a 2GB hard drive with at least 1.5GB of free disk space.
- Windows 2000 Datacenter Server—The vendor recommends eight Pentium III or better processors with at least 256MB RAM and a 2GB hard disk drive with 1.5GB free disk space.
- Windows Server 2003 Standard Edition—A 550MHz Pentium III or better processor is recommended with 256MB RAM and a 1.5GB hard disk drive with 1.5GB free disk space.
- Windows Server 2003 Enterprise Edition—A 733MHz Pentium III with 256MB RAM and a 2GB hard disk drive with 1.5GB free disk space.
- Windows Server 2003 Datacenter Edition—A 733MHz Pentium III with 1GB of RAM and at least 2GB hard disk drive with 1.5GB free disk space.
These recommended hardware requirements are the minimum needed to operate just the operating system. In today’s world with fast-changing technology, you probably can’t even buy a 166MHz Pentium from a computer vendor.
In addition to the base Microsoft hardware requirements for the operating system you are using, you are also required to take into consideration disk space requirements for installing Citrix MetaFrame Presentation Server 3.0 and all the ICA clients as follows:
- 250MB of disk space for MPS 3.0
- 150MB for installing all the ICA clients on the MPS server
Because MetaFrame Presentation Server will support multiple user logins to one server, server resources are needed to adequately service these users. When you are sizing your server hardware, it is very important that you have an idea of how many users will log in to each of your servers and also the types of users who will log in. When we say "types of users," we are trying to identify what the users will do when logged in to an MPS server. Typically, you can categorize users into two categories:
- Typical user—A typical user is one who logs in, uses one application at a time, and does not copy and paste many items between the ICA session and the ICA client.
- Power user—A power user is one who logs in and typically uses multiple applications at the same time and runs more advanced tasks.
A good rule would be to allocate twice the number of resources to a power user than you would for a typical user. By resources, we mean CPU and memory utilization.
Types of Applications
The types of applications installed on the servers have a great impact on the sizing of the servers. Some applications may be poorly written and may bog down an MPS server with as little as 10 users on it. If you are using a mixture of 16-bit and 32-bit applications, you may want to separate them on different servers to improve performance and responsiveness of each application and not allow a faulty application to affect another one.
On the flip side, well-written applications allow you to add more users. Thorough testing of an application using all its functionality is crucial prior to sizing the server’s resources.
Network Bandwidth Considerations
A robust, well-configured, and primed network can drastically improve application response and better the user experience. As we discussed in Chapter 2, "MetaFrame Presentation Server Architecture," one of the three components that make up the ICA protocol is the network, which is the transport mechanism by which data is exchanged. For this reason, it is important to avoid bottlenecks. Try the following to ensure higher performance on your network:
- Keep all Citrix MPS servers and Citrix-related servers on the same subnet to localize traffic and improve performance.
- Use Switched Ethernet when possible.
- Set the link speed to Full Duplex on your servers, the switch ports, and your ICA client devices for optimal performance.