High degrees of connectivity have resulted in systems that are crucial for enterprises, where failure can cause a whole division or the whole company to come to a complete stop. Furthermore, repairing these systems has become increasingly difficult if not impossible due to the complexity involved, regardless of whether these problems are due to soft- or hardware. With companies only able to cope with very short downtime, and repairs taking more and more time, they are faced with major challenges.
Unfortunately even a careful setup cannot guarantee fulfilling all of these extreme needs, nor is it cost-efficient. The main goal of todays infrastructure has thus shifted from assuring fail-safe operation to high availability. The fact is accepted that every device has the possibility of failure. Because of this redundant systems are installed that run in synchrony and take over all functions within seconds if the primary device fails.
A cluster of this kind has very few limits: whereas clusters of switches often lie directly next to each other, firewall clusters can be distributed across various data centers, so that availability can even be ensure in case of problems such as power outages. The cluster can be stretched across different countries or continents and equipped to work against any unforeseen problems, even if the number of devices increasy consistently.
Unfortunately, redundancy does come at a price, a fact those responsible for IT and the budgets involved know. Redundancy means purchasing two devices, but having only one online and running. What at a glance appears to be an empty investment turns out to be irreplaceable when the first incident occurs. Someone who has experienced large breakdowns knows, that losses through problems in IT can quickly end up more than purchasing replacement devices initially.
Redundancy is not for free. The truth which lies beneath this words is well known to every IT or financial team leader. To have redundant systems means, that one has to buy two devices but only one is online and working. Often people see dead money in such systems, investments that never pay out but in the first moment of a failure this infrastructure of high availability can prove itself more than priceworthy. Whoever had a front row seat during a big break down knows that damage caused by IT problems can easily exceed the costs of redundant devices by factors.