What is a Virtual Farm - What is High Availability
A server farm is a group of servers all working together to provide a service or application to the user. The key benefit to this among others is High Availability. A virtual farm is a group of servers that work together to host "virtual servers".
Why is this useful..?? If we need to perform maintenance or repairs on a server, or if one of these servers fails, the rest of the group of servers picks up the additional load, and your services will continue with virtually no interruption.
High Availability and redundancy are important in cloud computing and virtual servers because clients rely heavily on availability of the server resources.
Note: Make sure you ask your future provider about High Availability otherwise your systems may be interrupted when maintenance is carried out on the hardware.