This post describes the authors experience, almost losing his data on a RAID disk set. He also gives good details on why RAID is not a backup and how he rectified the situation. Remember: RAID is not a backup!
When working with corporate systems, a complete, reliable, and tested backup system is important. RAID does not protect you against many (or even most) disasters that could happen.
RAID is designed to protect against one thing: disk failure. It does not protect against user error, operator error, site destruction, and many more possibilities.
So how do I back things up? I must admit, I’ve improved my backup strategies of late. I currently have several tools that I use and would recommend to you:
- SpiderOak. This is an online backup service which offers the first 2Gb backup free. They also maintain multiple version backup, so if you want a file from two versions back, it’ll still be there. This service is worth paying for, I’d say.
- For my Mac, I’ve used PsyncX periodically (albeit not automated). It has come in handy more than once as my laptop died several times – I’ve one of those iBooks that was notorious for video hardware that failed annually (and Apple would fix for free, but never admitted fault). If you’ve a Mac, get an external drive and use PsyncX to save your home directory off. Also recommended: put your applications in your home directory, not the system directory: restoring your home directory will then be enough to get your applications back.
- For UNIX, the similar alternative to PsyncX is rsync: again, get an external drive and save your home directory off to it regularly.
- Also, come at it from the other direction: save your configuration by putting it into a cfengine or puppet setup and saving that as well. If the machine fails, running cfengine or puppet on startup will restore the system to its original state.
- One other item – that may seem a bit unusual – is using Thinkfree Office. Thinkfree Office gives you a way to save documents locally and have them mirrored in the Internet cloud – and you can also manipulate your documents on the web as well. Of course, this is only entirely true for documents that Thinkfree Office can edit.
It would seem that cfengine v3 is now available for download – that will have to be a subject for a new article.