You don??™t want to have to come into work just to send a message telling everyone
that your automated software is about to begin its task.
Fault tolerance can consume a lot of ground. A reliable environment is one that doesn??™t change.
For example, you might think that applying a patch to your software will make it more reliable
because the vendor has fixed the problem. Like the human body, every networked system is different.
Just as you can??™t guarantee that a new medication won??™t have disastrous side effects, you
can??™t guarantee that a patch will do anything other than make your system stop working. Even
though the hope is that things will go well and the application will run better than before, you don??™t
know about side effects until you??™ve thoroughly tested the new setup. Testing takes the guesswork
out of the system, makes it stable, and therefore more reliable.
As a final consideration for making your after hours processing more robust and reliable, think
about training several people to take over repairing the problem should you become unavailable.
In many cases, protectionist policies by those with knowledge (making them theoretically indispensable)
also serve to make the system completely unreliable.
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