The rise of server-based flash caching and other technologies like local performant storage pools, whether virtual storage appliances like the HP StoreVirtual VSA or VMware’s VSAN, marks a possible return to the days of the pizza box server in data centers across the world.
The pizza box server is a 1U unit that was the dominant server type before the rise of the blade format in the early nineties. Two of the drawbacks that caused its original demise were its lack of local storage capacity and its format. Then, the rise of the blade format, with the HP c7000 chassis being 10U in size and supporting sixteen half-height blades, saw an increase in density that allowed sixteen servers to serve resources in a space that previously only allowed ten. The blade format had other benefits as well, especially with the introduction of 10GbE and converged networking. Now a chassis could be serviced from just two 10GbE connections to the switching infrastructure. Taking into account remote management of the guests and chassis, an additional two Ethernet cables were required for iLO management. All are telling use cases for the blade format.
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