clustering

- Is a technology that provides fault-tolerant server and is similar to redundant servers, only difference is that in clustering each server takes part in processing services that are requested.


- Is a group of servers that are viewed logically as one server to users and it can be managed as a single logical system.

- Clustering provides for availability and scalability and improves performance.

- Combines different systems which are physically separated into logical one group.

- Cluster balance the traffic and perform the load balancing and user never came to know that they might be accessing different servers at different times.

- Clustering also known as server farms.

- For users this transparent and user will see only a single unit.

- In clustering all servers works simultaneously and if one server goes down the load will automatically gets transferred to another server without knowing to user although there can be slight delay in performance.

- While in case of when we use secondary server, this server stays idle and in passive mode which can be waste of resources, but clustering takes advantages of all the servers.

- Clustering offers load balancing, availability, redundancy, and failover.