Friday, August 19, 2011

Clustering in Linux

When one than one computer work together to perform a task, its known as Clustering.

There are four type of cluster

• Storage

• High availability

• Load balancing

• High performance

Above given type of clustering is basically based on objective of clustering.

Storage clusters provide a consistent file system image across servers in a cluster, allowing the

servers to simultaneously read and write to a single shared file system. A storage cluster

simplifies storage administration by limiting the installation and patching of applications to one

file system. Red Hat Cluster Suite provides storage clustering through Red Hat GFS.

High-availability clusters provide continuous availability of services by eliminating single points

of failure and by failing over services from one cluster node to another in case a node becomes

inoperative. Red Hat Cluster Suite provides high-availability clustering through its High-availability Service Management component.

Load-balancing clusters dispatch network service requests to multiple cluster nodes to balance

the request load among the cluster nodes. Node failures in a load-balancing cluster are not

visible from clients outside the cluster. Red Hat Cluster Suite provides load-balancing through

LVS (Linux Virtual Server).

High-performance clusters use cluster nodes to perform concurrent calculations. A

high-performance cluster allows applications to work in parallel, therefore enhancing the

performance of the applications. (High performance clusters are also referred to as

computational clusters or grid computing.)