FRU

Field Replaceable Unit (FRU): Any hardware that can be replaced "in the field"; i.e., without shipping the entire system chassis back to the manufacturer. This includes small modules (socketed CPU nodules, RAM DIMMs, PCIe cards) all the way through system planars (also known as "mainboards" or "motherboards" outside of IBM specific terminology). When used in an IBM-specific sense, presence of a CFAM diagnostic port may be indicated, e.g. on CPU modules.