All front-end servers you plan to include in the cluster will need to be running Windows 2000 Advanced Server or Windows Server 2003. You will also need an Exchange Server license for each front-end server.
NLBS clusters also require two IP addresses for each cluster. While these two IP addresses can technically be bound to a single NIC, I strongly recommend using two NICs. Having multiple NICs in each server makes setting up the cluster a little less complicated and tends to improve cluster performance.
One of the NICs will be assigned a shared IP address that every node in the cluster will use. The other NIC will be assigned a unique IP address. When a user attempts to communicate with the NLBS cluster, the DNS server will direct the request to the shared IP address. The NLBS will then send it to one of the individual cluster nodes using the unique IP address.
As for hardware, Windows isn't too picky about what you use for cluster nodes. Pretty much any hardware will do, as long as it's compliant with Microsoft's Hardware Compatibility List. The front-end Exchange Server cluster nodes don't even have to match each other in terms of hardware.
TUTORIAL: HOW TO SET UP A FRONT-END EXCHANGE SERVER CLUSTER
A lesson in cluster node configuration and consistency
Pros and cons of a Network Load Balancing Service front-end cluster
Requirements for a Network Load Balancing Service front-end cluster
How to set up a Network Load Balancing Service front-end Exchange cluster
The pros and cons of a DNS-based front-end Exchange cluster
How to set up a DNS-based front-end Exchange cluster
Related links from SearchExchange.com
|ABOUT THE AUTHOR:|
| Brien M. Posey, MCSE
Brien M. Posey, MCSE, is a Microsoft Most Valuable Professional for his work with Exchange Server, and has previously received Microsoft's MVP award for Windows Server and Internet Information Server (IIS). Brien has served as CIO for a nationwide chain of hospitals and was once responsible for the Department of Information Management at Fort Knox. As a freelance technical writer, Brien has written for Microsoft, TechTarget, CNET, ZDNet, MSD2D, Relevant Technologies and other technology companies. You can visit Brien's personal Web site at http://www.brienposey.com.