Redirect to offsite server during downtime

[pgentoo]

I just had a bit of downtime due to issues out of my control at my datacenter and it got me thinking...

In this case, all clients simply get server timeouts. DNS could easily be switched for all the websites, to point to some other IP address, which has a "Server under maintenance" page. This would at least give some feedback to the user that the site does exist, something is temporarily wrong, and it will be fixed soon.

I have some scripts to update all the serials on my standalone nameserver, but I didn't have scripts written to update all the ip's in the bind files, to point to another common IP. I was thinking this could just be done on a copy of the files, and then the named.conf adjusted to include the modified zones instead of the normal ones. Once the server is backup, then named could be switched back to the original configuration and the temporary zones discarded.

I want to put together some scripts to do this, but I figured others must already be doing similar stuff, and maybe I could just leverage something already written.

It would be even nicer, if when ispcp generates its bind conf, it could generate two sets of zone files, one for normal operation, and one for a disaster scenario like mentioned above. All these zones could point to some offsite server that should never be down at the same time as the core servers. Then the only change would be to tell bind to load the "maintenance" set of zones, instead of the normal ones.

Thoughts? Ideas? Someone want to write it?

Thanks,
pgentoo