Linux.com: Taking a Load Off: Load Balancing with Balance

“A server is limited in how many users it can serve in a given
period of time, and once it hits that limit, the only options are
to replace it with a newer, faster machine, or add another server
and share the load between them. A load balancer can distribute
connections among two or more servers, proportionally cutting the
work each has to do. Load balancing can help with almost any kind
of service, including HTTP, DNS, FTP, POP/IMAP, and SMTP. There are
a number of open source load balancing applications, but one simple
command-line load balancer, balance, remains one of the most
popular available.

“Ideally you should install a load balancer on a dedicated
machine that can handle all the incoming connections, with a
separate network interface for internal and external connections.
However, none of this is necessary for the purposes of this
article..”

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