Purchase quality server and network hardware to build a fault-tolerant system. The proper configuration of this hardware is equally important.
Create disk subsystem redundancy using RAID.
Don't attempt to run both MSCS and NLB on the same computer because Microsoft does not support them due to potential hardware-sharing conflicts.
Use cluster-aware applications so that the cluster service can monitor the application. A cluster-unaware application can run on a cluster, but the application itself it not monitored by Cluster Service.
Use active/passive clustering mode except in cases where performance is critical. Active/passive mode is easier to manage and maintain, and the licensing costs are generally lower.
Use NLB to provide connectivity to TCP/IP-based services such as Terminal services, Web sites, VPN services, and streaming media services.
Use Windows Server 2003 Cluster Services to provide server failover functionality for mission-critical applications such as enterprise messaging, databases, and file and print services.
Disable power management on each of the cluster nodes both in the motherboard BIOS and in the Power applet in the operating system's Control Panel to avoid unwanted failover.
Carefully choose whether to use a shared disk or a nonshared approach to clustering.
Always purchase one additional node when planning for an MNS cluster.
Be sure that both Microsoft and the software manufacturer certify that third-party software packages for Cluster Service will work on a Windows Server 2003 cluster; otherwise, support will be limited when troubleshooting is necessary.
Use multiple network cards in each node so that one card can be dedicated to internal cluster communication (private network) while the other can be used only for client connectivity (public network) or for both public and private communication (mixed network).
Configure the failback schedule to allow failback only during non-peak times or after hours to reduce the chance of having a group failing back to a node during regular business hours after a failure.
Thoroughly test failover and failback mechanisms.
Do not change the Cluster Service account password using the Active Directory Users and Computers snap-in or the Windows security box if logged in with that account.
Be sure that a majority of the nodes remain running to keep the cluster in a working state if you're removing a node from an MNS cluster.
Carefully consider backing up and restoring a cluster.
Perform ASR backups periodically and immediately following any hardware changes to a cluster node including changes on a shared storage device or local disk configuration.
Thoroughly understand the application that will be used before determining which clustering technology to use.
Create a port rule that allows only specific ports to the clustered IP address and an additional rule blocking all other ports and ranges.
Employ tools such as Robocopy.exe, which are located in the Windows Server 2003 resource kit or Application Center, to replicate data between NLB nodes.
