Introduction to load balancing
In its simplest form, load balancing is all about spreading client load across multiple servers. These servers can be in one or several locations, and the method of distributing that load can vary quite a bit. In fact, how successful you are in spreading that load evenly can vary quite a bit as well (mostly depending on the method chosen). Let's explore some of the more common methods of load balancing.
Round Robin DNS (RRDNS)
You can do simple load balancing just with a DNS server, in what's called Round Robin DNS (RRDNS). In this configuration, as clients request to resolve the a.example.com
hostname, the DNS server will return the IP of Server 1; then, when the next client requests it, it will return the IP for Server 2, and so on. This is the simplest load balancing method and works equally well for both co-located servers and servers in different locations. It can also be implemented with no changes at all to the infrastructure &...