If you’ve ever claimed 24×7x365 availability of your server, and you think it’s easy because you setup the database replication and keep the uptime for certain length of time, you’re wrong. That isn’t about high availability, that’s called lucky. I have met people who thought with current cheap and powerful intel server, plus free softwares (may be MySQL replication), they could easily achieve 24×7x365 (and of course they aren’t aware of all the exhaustive details of power/data/connection availability, it’s not even get to testing yet).
Go read this, Jeremy quoted Michael Conlen’s well written and easy to understand response of high availability (in MySQL mailing list).
Reading Summary - Jan 19, 2006
Snakes and Rubies Talk - Jan 08, 2006
Symantec - Dec 28, 2005
Weekend Tech-and-reading activities - Dec 04, 2005