How does MSCS help administrators do “rolling upgrades” of their servers?
With MSCS, server administrators no longer have to do all their maintenance within those rare windows of opportunity when no users are online. Instead, they can simply wait until a convenient off-peak time when one of the servers in the cluster has enough horsepower for all of the cluster workload. They then point-and-click to move all the workload onto one server, and they’re ready to perform maintenance on the unloaded server. Once the maintenance is complete and tested, they bring that server back online and it automatically rejoins the cluster, ready for work. When convenient, the administrator repeats the process to perform maintenance on the other server in the cluster. This ability to keep applications and data online while performing server maintenance is often referred to as doing “rolling upgrades” to your servers.
