Thursday, March 24, 2011

Load balancing

In networking, load balancing is a technique to distribute workload evenly across two or more computers, network links, CPUs, hard drives, or other resources, in order to get optimal resource utilization, maximize throughput, minimize response time, and avoid overload. Using multiple components with load balancing, instead of a single component, may increase reliability through redundancy. The load balancing service is usually provided by a dedicated program or hardware device (such as a multilayer switch or a DNS server).
F5 Networks originally manufactured and sold some of the very first load balancing product, called BIG-IP. If a server went down or became overloaded, BIG-IP directed traffic away from that server to other servers that could handle the load.
F5's BIG-IP product is based on a network appliance (either virtual or physical), which runs F5's Traffic Management Operating System (TMOS), which runs on top of Linux. This appliance can then run one or more product modules (depending on the appliance selected), which provide the BIG-IP functionality.