: When talking about web servers, what is a « cluster » ?


: When talking about web servers, what is a « cluster » ?

In: Technology

A cluster is multiple computers that work as a unit.

If your traffic is too large for one computer to handle, you use some sort of load balancing scheme to distribute that traffic amongst multiple computers. A cluster also can act as a failsafe, if one computer goes down, the others stand ready to take on its load.

Clustered web hosting is when instead of having just one web server providing the service you have multiple physical machines sharing responsibility for the load. This both ensures your website can handle more requests at once and prevents services taking resources away from each other, but also makes sure that even if a computer goes down the website as a whole still stands strong.

Imagine you have 4 computers or nodes serving your website. There might be a fifth computer sitting in front acting as a load balancer: it will grab all the requests coming in, and try to evenly spread them across the 4 computers so that none of them get overloaded and the website can have more clients served at once.