I think z/VM allows a virtual CF. From an older zPDT Redbook. A new level of the Coupling Facility code is included, which is level CFCC D93G R17 SL4.8. This CFCC level is considerably larger than the CFCC included in the previous zPDT release and a larger z/VM guest is needed to use it. (We now suggest a z/VM guest size of at least 512 MB for a CFCC guest.)
Sent with Proton Mail secure email. On Friday, June 21st, 2024 at 12:20 PM, Seymour J Metz <[email protected]> wrote: > z/VM allows you to connect multiple virtual machines with virtual CTCAs. > > -- > Shmuel (Seymour J.) Metz > http://mason.gmu.edu/~smetz3 > עַם יִשְׂרָאֵל חַי > נֵ֣צַח יִשְׂרָאֵ֔ל לֹ֥א יְשַׁקֵּ֖ר > > ________________________________________ > From: IBM Mainframe Discussion List [email protected] on behalf of > Mike Schwab [email protected] > > Sent: Friday, June 21, 2024 11:49 AM > To: [email protected] > Subject: Re: GRS in MONOPLEX without physical CTCs ? > > Can z/VM do this? Costs? > > On Fri, Jun 21, 2024 at 8:45 AM MANCINI Frédéric (80) > [email protected] wrote: > > > Actually, we do share a few DASD devices between our lpars. > > > > Thanks to all the replies, I understand better now what we must do in > > order to implement a fully functional GRS without buying an external > > coupling facility. > > > > I understand that we can leave our lpars in MONOPLEX mode and use GRS > > managed CTCs, possibly on a ring architecture in order to minimize the > > hardware connections. > > > > Using virtual CTCs without interconnecting the MONOPLEX lpars doesn't > > seem to make sense for resource serialization. > > > > Am I right ? > > > > ------------------------------------------------------------------------ > > De : Tom Marchant [mailto:[email protected]] > > Envoyé : vendredi 21 juin 2024 à 15:30 > > Pour : [email protected] > > Objet : GRS in MONOPLEX without physical CTCs ? > > > > > The OP hasn't said whether or not any DASD is shared. > > > > > > If there is a need to share PDSE, it is only supported within a Sysplex. > > > MIM is not sufficient > > > > > > -- > > > Tom Marchant > > > > > > On Fri, 21 Jun 2024 13:49:29 +0200, Radoslaw Skorupka > > > [email protected] wrote: > > > > > > > To complement: > > > > Parallel Sysplex - a CF is required, which mean sysplex links (emulated, > > > > free - for PS within single CPC). GRS is STAR mode is possible and > > > > strongly suggested. (GRSplex is required, the mode is suggested). > > > > > > > > Base Sysplex - CTC links required. In the old days also sysplex timer. > > > > Now it can be sysplex link to provide time synchronization for STP > > > > (Server Time Protocol). The GRS is mandatory and it's configuration is > > > > RING, which is not the best from performance point of view. For base > > > > sysplex within single CPC there are no STP-only links, but CTC over > > > > FICON is required. Note: the FICON can be shared, that means used for > > > > other purposes. > > > > > > > > Monoplex. GRSplex is still possible (unless something changed) and it is > > > > RING topology with drawbacks mentioned above. Of course multiple > > > > monoplex LPARs may share DASD without GRSplex, but again it is not > > > > seamless - at least PDSE sharing is almost impossible. > > > > > > > > ...and there is CA-MIM family of products. :-) > > > > > > > > -- > > > > Radoslaw Skorupka > > > > Lodz, Poland > > > > > > > > W dniu 21.06.2024 o 08:41, Brian Westerman pisze: > > > > > > > > > You can just use extra FICON interfaces as FCTC's. IBM refers to that > > > > > method as a baby sysplex. It allows you to have GRS in ring mode. TO > > > > > have star mode you need CF's. > > > > > > > > > > If you have multiple LPARs and you share dasd, then you need either > > > > > CF's (expensive) or Ficon CTCs (pretty cheap). The setup is very > > > > > simple. CF's are much faster but ficon CTC's easily handle 3,4 or 5 > > > > > lpars without any issues at all. > > > > > > > > > > Brian > > > > > > > > > > ---------------------------------------------------------------------- > > > > > For IBM-MAIN subscribe / signoff / archive access instructions, > > > > > send email to [email protected] with the message: INFO IBM-MAIN > > > > > ---------------------------------------------------------------------- > > > > > For IBM-MAIN subscribe / signoff / archive access instructions, > > > > > send email to [email protected] with the message: INFO IBM-MAIN > > > > > ---------------------------------------------------------------------- > > > > > For IBM-MAIN subscribe / signoff / archive access instructions, > > > > > send email to [email protected] with the message: INFO IBM-MAIN > > > > ---------------------------------------------------------------------- > > For IBM-MAIN subscribe / signoff / archive access instructions, > > send email to [email protected] with the message: INFO IBM-MAIN > > > > > -- > Mike A Schwab, Springfield IL USA > Where do Forest Rangers go to get away from it all? > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN > > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
