Web App: High Availability / How to prevent a single point of failure?

load-balancing high-availability cluster-computing uptime
nickb picture nickb · Oct 30, 2011 · Viewed 18.4k times · Source

Can someone explain to me how high-availability ("HA") works for a web application ... because I assume HA means that there exist no single-point-of-failure.

However, even if a load balancer is used- isn't that the single point of failure?

Answer

user677686 picture user677686 · Mar 7, 2013

I have found this article on the subject: http://www.tenereillo.com/GSLBPageOfShame.htm

Basically if you do not require long lasting sticky sessions you can configure your DNS servers to return multiple A records (IP addresses) for your website.

Web browsers are smart enough to try all the addresses until they find one that works.

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