Not all that long ago, maintaining firmware and software compatibility among different pieces of data center tech was a fairly easy affair. Upgrading your OS? No problem, a quick check of a compatibility guide would tell you whether your server's BIOS or RAID controller needed to be upgraded. Installing a SAN? You might need to check to see that your existing FibreChannel host-based adapters and switches were at a compatible revision first.
Even in cases where multiple components were cross-dependent (such as in a FibreChannel SAN), sussing out the compatibility issues wasn't terribly complex -- usually a single compatibility matrix provided by the hardware manufacturer would get you what you needed.
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Since then, the industry has seen both virtualization become more ubiquitous and a steady push toward compute, network, and storage convergence. Although I don't dispute the potentially enormous benefits of both virtualization and convergence, the increasing degree of integration between different layers of data center tech has substantially complicated the task of keeping everything current and compatible.