<snip> What CPU's were involved with each level, and what was the real underlying item changed on the CPU that forced a new level? </snip>
No one seems to have answered Tony's question. For z/OS V2R1 and onward, the information can be found in z/OS Planning for Installation -> Preparing the target system -> Identifying hardware requirements for the target system -> Identifying server requirements https://www.ibm.com/support/knowledgecenter/SSLTBW_2.4.0/com.ibm.zos.v2r4.e0zb100/osproc.htm which has Table 1. Minimum server levels and machine facilities that are required for z/OS Then, older than that -- z/OS 1.6 introduced the requirement for z/Architecture. -- MVS/ESA 3.1.0 introduced the requirement for ESA Architecture. -- MVS/XA 2.1.0 introduced the requirement for XA Architecture. Maybe there were some others in the middle of these older ones but nothing comes to mind. In general, ALS's are to a set of functions, not to a particular machine. A particular machine will satisfy those functions, but the ALS does not mean that it is OK to assume you can use all the functions of that machine. Peter Relson z/OS Core Technology Design ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
