I have a client that is using Rackspace.com to host both their website and their hosted Exchange mail. Client's website is very heavily trafficked and it's really important that it have close to 100% uptime. A couple of weeks ago (due to some problems experienced by Rackspace) the website went down for a few hours. And thanks to Murphy's Law this happened right while they were doing an important pitch to a large prospective client!
So now my client wants to know if there is some way to implement a Plan B if Rackspace experiences this kind of problem again in the future.
They were suggesting setting up a backup webserver in their office they could be brought online in the event of a future outage, but this doesn't sound like a good strategy given that there would be no way to fully test it out until the next outage.
What do other companies do to guard against this sort of problem?