On Mon, 10 May 2021 22:35:50 -0500, Alan Altmark <[email protected]> wrote:
(snippage) > >z/VM 3.1 was the last release to support 370 mode virtual machines, including >CMS. z/VM V4 (all releases) tolerated virtual machines defined with MACHINE >370, but would not instantiate them. (This was done in case of sharing a >directory with z/VM V3 or earlier.) The 9672 G3 was the last machine with >370 microcode, and z/VM 3.1 was the last release to support the G3. > (end snippage) > >Sir Alan >Lord of the Protocols >Order of the Knights of VM > Since we are talking history here, I need to make a meticulous point. While I cannot recall for sure if an S/370 mode CMS would IPL in a 370 mode virtual machine under z/VM 3.1 CP, I can say for sure that other 370 mode guest operating systems (e.g. VM/SP and VSE/SP) would *not* IPL under z/VM 3.1 CP in an S/370 mode virtual machine as it was originally released. You had to apply PTF UM30003 for APAR VM62843 to CP before an S/370 guest of z/VM 3.1 would IPL or you weren't going anywhere and had an immediate failure from the guest IPL command. One can speculate on how or why such a significant failure in function made it out the door in the last release to support 370 mode guests. I took calls from customers at the time claiming this must be a FLEX-ES problem, when it was in fact just a CP software error that they had to fix by calling IBM and ordering the fix. Sir Gary The Meticulous Order of the Knights of VM ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
