We've upgraded DASD subsystems several times over the years. As I whined several months ago, the process is complicated here by a chronic over-supply of smallish volumes that need to be replicated to the new hardware one way or another. (Consolidating smaller volumes into larger 3390x units would solve the problem, but that would be hugely disruptive to applications; a very hard sell.)
This upgrade required moving thousands of 3390 volumes to new unit addresses in the new subsystem, which mandated IPLing with a new IODF. We had earlier done this with a subset of DASD dedicated to sandbox and development, so we had a few LPARs that did not need to be changed again. These unaffected LPARs were all located on one CEC, but we had a second CEC whose LPARs were all affected by the change. So following the procedure outlined by Mike below, we copied all (remaining) volumes via PPRC. We then had to IPL all affected LPARs with a new IODF. On the CEC with unaffected LPARs, we ACTIVATEd the new IODF via OS command. On the other CEC, however, where we had no unaffected LPARs, we had to POR to get the new IODF into HSA before IPLing. This sounds complicated, but it was all planned and orchestrated over several months. The big-bang cutover itself lasted only a few hours. DR DASD was resynched within another few hours, so we had minimal exposure to data center failure. Most of the heavy lifting was performed by my colleagues, who deserve *huge* credit for conceiving and executing the plan. . . J.O.Skip Robinson Southern California Edison Company Electric Dragon Team Paddler SHARE MVS Program Co-Manager 323-715-0595 Mobile 626-543-6132 Office ⇐=== NEW robin...@sce.com -----Original Message----- From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On Behalf Of Mike Schwab Sent: Saturday, June 15, 2019 1:37 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: (External):Re: Volume compare utility Usually you can create the PPRC pairs, give the devices time to catch up the replication, then shut down, wait for replication to complete, swap the PPRC pairs to the new device, and IPL from the new devices with one hour or less additional downtime over your normal IPL times. On Sat, Jun 15, 2019 at 4:56 PM Jesse 1 Robinson <jesse1.robin...@sce.com> wrote: > > Thanks! > > . > . > J.O.Skip Robinson > Southern California Edison Company > Electric Dragon Team Paddler > SHARE MVS Program Co-Manager > 323-715-0595 Mobile > 626-543-6132 Office ⇐=== NEW > robin...@sce.com > > -----Original Message----- > From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On > Behalf Of Jerry Whitteridge > Sent: Friday, June 14, 2019 4:16 PM > To: IBM-MAIN@LISTSERV.UA.EDU > Subject: (External):Re: Volume compare utility > > Good to hear it went well Skip > > Jerry Whitteridge > Delivery Manager / Mainframe Architect GTS - Safeway Account > 602 527 4871 Mobile > jerry.whitteri...@ibm.com > > IBM Services > > IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> wrote on > 06/14/2019 03:44:07 PM: > > > From: Jesse 1 Robinson <jesse1.robin...@sce.com> > > To: IBM-MAIN@LISTSERV.UA.EDU > > Date: 06/14/2019 03:44 PM > > Subject: [EXTERNAL] Re: Volume compare utility Sent by: IBM > > Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> > > > > This thread was originally motivated by needing to move from an > > older > > DS8 subsystem to a new one. We've done this repeatedly over the > > years with a combination of utilities and IPLs spread over several months. > > The goal this time was to do it in a big bang allowing for several > > hours of down time but otherwise all in one single window. The > > problem with our old way of doing things was that we would encounter > > many separate periods of DR risk where we could not recover the > > entire production environment. This time, by using PPRC with all > > systems down, there was no risk window since no data updates could > > occur in the meantime. > > > > I'm happy to report that the new procedure worked. We abandoned the > > idea of 'comparing volumes' as taking too long with minimal payback. > > We shut it all down, synched up data volumes via PPRC, and IPLed > > everybody with an IODF that contained the new DS8 in place of the old. > > It went even smoother that we hoped for. Lots of planning and desk > > checking, no serious oversights. > > > > Thanks to all who contributed to this project! > > > <snip> Mike A Schwab, Springfield IL USA ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
