One of the little known or little explored secrets with servers running VMware ESXi 5.x is they can be booted off of USB or SD flash media. In such a scenario, enterprises could dump HBAs or RAID cards and the hard drives or SSDs that are used to boot the servers. Going this route yields a CAPEX benefit for new systems, the cost of flash media for boot is insignificant compared to the drives and storage adapter cards required to spin up a server. There are also gains in OPEX; the implications of moving to USB or SD flash media have a big advantage when considering the power required for a small flash media drive for boot vs. the more common practice of adapters and drives.
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