Many large enterprises still run critical applications on legacy Linux and Unix platforms. Much like the fabled Energizer Bunny, these old computing OSes keep going and going and going. Some of these are not even in production any more. Upgrading these systems is no simple matter, partly because the organizations using them cannot simply turn off servers containing customer or financial data. Still, ever-increasing regulatory agency edicts to safeguard customer data often require some level of retrofitting to remain compliant.
