Low yield nuclear warhead destroying site - not a lot I can do about that
Well any small business DR plan Can Not Address this type of Thing!
But there are things you should be thinking about Flood so are all your Mission Critical Servers above any possible Flood Levels? Fire what would happen if there was a fire in one of the buildings could it spread to both? Could the fire suppression systems in these buildings render all the hardware unusable after the fire was put out?
If you answer to any one of these questions is No then you really do not have a Valid DR Plan in Place! All that you do have is some means of recovering after a Hardware Failure which is an expected thing to happen but so far you have not addressed any Unexpected but Possible things that can and do happen.
If you are on a coast are you're systems far enough inland to be Tsunami Proof? Do you live in an area that is Earthquake Prone? So what then would happen if the worst was to happen? Is your Hardware sufficiently protected so that you can recover your data and be up and running with all Begged, Stolen or Borrowed Hardware?
Forget about the unlikely which the current Governments push on us to keep us worried and under control and think along the lines of the likely occurrences that are possible now.
If you where to blindly follow the Fear Campaign by the Governments there is no need for any form of DR Plan as you would expect to be dead along with at the very least the entire set of building in the local or even maybe the entire city. While it's possible it's also Highly Unlikely to occur so look at what Nature can throw at you and plan accordingly.
The first thing that I do in forming an DR Plan for any business is to grab a copy of the last Major Flood Levels and then work according to what these levels where and add another 25% as a safety margin so if the business falls within that area they can expect to have a total system loss and the need for Off Site Storage is necessary. According to statistics this will be a Once in a 100 Year Event that last one was now 32 years 6 months ago so while we have a bit of breathing room it's also possible that next week this area will be underwater.
Are the area that you are in Subject to Flash Flooding? if that's the case can you keep water out of your Server Rooms with a total Power Failure? If not WHY? Have any new buildings been put up recently that may adversely affect the way that rain water can flow away during a severe storm that will cause Localised Flooding?
It's totally useless to hold a RAID Array in your hand that's been underwater for even as little as 30 minutes as all the drives will be trash and you'll be paying someone to recover the data and waiting for it as well most likely. This depends on how Localised the flooding was from the rain the more widespread the more HDD that the Data Recovery Houses will have to work with so the longer your wait will be.
Winchester Drives don't take kindly to being submerged so you have to plan according to the limits of your hardware just saying I have a copy in another building close by may not be enough particularly if they are close together and subject to the same events. If you had a mid range Earth Tremor just how stable would the buildings that house this Hardware be?
Have you thought of things like this rather than throw your hands in the air and worry about a Fission Weapon being deployed that will make it all a useless exercise?
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