IBM introduced IFLs on September 29, 2000. At the same time, IBM introduced a special Linux-only VM-like product, called the S/390 Virtual Image Facility for Linux, to cater to IT staff previously unfamiliar with IBM mainframes. IBM soon discovered that z/VM was not too difficult for new IT staff to learn (and worked better), so IBM discontinued S/390 Virtual Image Facility for Linux in April 2002.
IFLs are available for all IBM mainframes as far back as the G5 series. Fujitsu and Hitachi also offered IFLs on certain models. An IFL is not required to run Linux — Linux runs on general purpose processors (CPs) as well. IFLs simply cost less.