“Simple” Failover to a Geographically Separated Server?

Question

I've been reading about DNS failovers and a bunch of other technical terms however I'm a bit of a newbie in this so it all sounds Greek to me. Basically here's what I just need:

I have two shared hosting accounts from two different providers (Server A and Server B). Each of this accounts contain exactly the same website content.

On a normal day, typing my domain name should point to the IP of Server A. But on a bad day in which Server A is down or unreachable, my domain name should point to the IP of Server B in the fastest way possible.

How do you achieve this and what services can you recommend if any? Thanks.

Answer 1

The simple answer is to use a content distribution/delivery network to handle your traffic. They already have the infrastructure in place to handle failover like this.

If you must host it yourself, one route to take is this:

• Set the DNS TTL very low
• Set up a server which monitors the web servers
• If one of the web servers goes down, automate a script on the monitoring server to modify the DNS and remove the failed server

My first recommendation is still to use a CDN, though.