Hi List, First of all, thanks everybody for your assistance.
Second, just to close this, I followed John's recommendation about recycling the CATALOG address space to pick up the ability to use extended GDGs. Yes, I did this off hours when there was very little running on the machine and it worked fine. After the capability was in place via the catalog address space cycle, I was able to uncatalog all the virtual tape generations, redefine the GDG base as extended, and recataloged all the tapes to the redefined GDG. All worked as advertised. Users are happy they can now access their old stuff which makes me happy too. :-) Thanks everybody, again. Rex -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of John Eells Sent: Tuesday, August 29, 2017 2:55 PM To: [email protected] Subject: Re: extended GDG implementation Pommier, Rex wrote: > Hello list, > > I have what are probably simple questions regarding the relaxation of the 255 > generation GDG limit. We are running z/OS 2.2 so are eligible for the > relaxation. I know I need to make a change to the IGGCATx member to activate > the capability and I need to add EXT to the GDG definition. So here are my > (rather basic) questions. > > 1. Can I implement an IGGCATxx member short of an IPL? I don't have one > now, relying on the defaults, and I don't see anything in the INIT&TUNING > manual that indicates that I can implement this dynamically, sadly. > > 2. Once it is active, can I use an IDCAMS ALTER to change between the old > limit and an extended one? I am positive the answer to this is "no, it can > only be done at GDG definition time" but am hoping. > > 3. Here's the scenario that has led me to this point. We just discovered we > have a tape based GDG defined with LIMIT(255) and we have had several > generations fall off the end. This is data we need to recover. Presuming > the answer to question 2 is "no" as I strongly suspect, does anybody see an > unsurmountable problem with (carefully) uncataloging all the tape > generations, redefining the GDG base as extended with an appropriate limit, > and recataloging all the generations, including the ones that have fallen off? > <snip> For (1), Managing Catalogs says, "The system applies IGGCATxx values at IPL time as well as at the restart of the Catalog Address Space." You can restart Catalog using F CATALOG,RESTART. Be aware that Catalog operations will be suspended for a bit while that happens. For (2), I don't see an ALTER keyword that would do that, nor the Extended attribute (for GDGs) in the alterable attribute list, in Access Method Services Commands. For (3), I don't, but I'd want to try a test case or two first! -- John Eells IBM Poughkeepsie [email protected] ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] 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 [email protected] with the message: INFO IBM-MAIN
