When we build high-availability systems we have to reduce component failure below a tolerable threshold. To determine if our designs are achieving our aims we have, typically, run simulations of failure-scenarios and then observed how our simulated designs cope. After all; we can’t deploy a real system and then just flick-the switch to see how it fails; can we?
The answer to that last question has always been no because a real-world deployment would place resources in jeopardy and be financially restrictive. One facet of cloud computing’s game-changing nature is that it makes a real-world deployment low-cost and easy. Deploying a real-world system is possible and we can ‘flick-the-switch’ to see how it behaves. it’s a strange notion when you’ve been raised on simulation.
Recall your last customer incident involving a deployed system; did you have a test-case that could have exposed the defect? Could building a real-world simulation in the cloud provide a viable means to test your system? Did you not test a scenario because it was too expensive using real-systems?
Posted by robertmacgregor 
