The unsolvable problem is that there are hundreds of millions of separate things that will go wrong, if we're talking about all computers worldwide. Any one of these hundreds of million of things can generate repetitions. Think of Medicare checks: 80 million a month.
No one can accurately forecast all of the things that will go wrong. All we know is that millions of things will go wrong. Any one of them could be catastrophic for a company. Cash flow is not automatic -- especially if the banks go down.
The author is Geoff Palmer. He understands the problem.
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The problem is that you almost certainly don't know just where these failures will occur and until you do, youíre playing a form of blind-folded Russian roulette. Consider the scenario where a mainframe fails to handle year 00, (a disturbingly common scenario, I should add). In considering just three of the probable outcomes, we get three very different business implications. What would happen to your operation if ...
Every password on the system is suddenly treated as expired (Typical problem rating:- Low.) (Implications:- Inconvenience only.)
Automated operations stop running. (Typical problem rating:- Medium.) (Implications:- Potentially serious if they canít be restarted.)
All your product licences expire, rendering them unusable. (Typical problem rating:- Critical.) (Implications:- Disastrous.)
So a single, simple failure could just irritate your staff or wipe out your company. (And by the way, if your answer to the third one was to call the vendor's helpdesk, bear in mind they've probably been inundated with similar calls or completely wiped-out because they use the same mainframe.)
Unlike a traditional disaster recovery exercise, recovery may not be possible for days or weeks or even, if your vendor's long since left the scene, not at all. When a major airline suffered a serious fire in its main computer room some years ago, it took 17 hours to get the system running again. In just another four hours, the company would have been technically insolvent because of the interruption to its cashflow.