Tony, Thank you for setting me straight on the lack of requirement of all volumes in an LCU being the same size. I'm pretty sure my business partner had told me that was a requirement. It may have been a restriction from long ago. Our first emulated device was a DS6800 that was replaced by a DSD8870 then to a DS8910F. Is it possible that was a requirement in the early days of the DS6800 level and we just kept the idea even though the requirement vanished?
Rex -----Original Message----- From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On Behalf Of Tony Thigpen Sent: Monday, September 11, 2023 12:21 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: [EXTERNAL] Re: Storage questions - mod9, mod27, mod54 Linda, Really, you need to take those questions to your storage group. There are a lot of variables based on hardware and currently used storage in the DASD subsystem. To fix one incorrect reply, at lease on IBM DS8000, all DASD on the same LCU (FKA 'string') does *not* have to be the same size. It makes it easier for the storage group to manage if they are all the same, but it's not required. The DS8000 allocates storage in Mod-1 slices. You current addresses only have enough slices for their current size. Converting from one size to another requires deleting a volume and redefining it. The rest of the volumes don't have to be touched. There is a limit on how many slices each DS8000 is licensed for. If there are free slices, then the storage group can define you some new volumes to which you will migrate your data to. Then, they can reclaim the original slices. (Note: This leaves 'holes' in the CUU address range and some people don't like that.) Talk to your storage group. They will tell you if they can create new volumes then the data can be migrated. Or, they may require a full back-up and re-load if they don't have free slices in the DS8000. Tony Thigpen Linda Hagedorn wrote on 9/11/23 10:14 AM: > Hi, > > I hope you won't mind a storage question. > > We're running zOS 2.4 and have a smattering of volume sizes - mod9, mod27, > mod54. > > I'd like to have all mod54's for Db2 and be prepared before going to the > storage folks. > > 1. Is storage virtual nowadays? > 2. Can virtual mod9s and mod27s be reconfigured to mod54s? > 3. Does the reconfiguration require an IPL? > 4. Does the reconfiguration new addressing in IODF? > 5. Is the storage vendor (IBM, EMC, etc.) relevant? Does the hardware > determine or be a factor in merging the mod9s/mod27s, into mod54s? > 6. Is it a given that the volumes must be cleared/emptied before the > reconfiguration happens? > 7. How long does reconfiguration take? > > Is there anything else I should consider before taking this request to the > storage group? > > Any information or advice is appreciated. > > Thank you. Linda Hagedorn > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, send > email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- The information contained in this message is confidential, protected from disclosure and may be legally privileged. If the reader of this message is not the intended recipient or an employee or agent responsible for delivering this message to the intended recipient, you are hereby notified that any disclosure, distribution, copying, or any action taken or action omitted in reliance on it, is strictly prohibited and may be unlawful. If you have received this communication in error, please notify us immediately by replying to this message and destroy the material in its entirety, whether in electronic or hard copy format. Thank you. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
