This is a point that David missed. As Stephen says, you lose virtual RESERVE/RELEASE, something that could be disastrous if you have guests that depend on R/R, such as MVS or its progeny, sharing the disks. True, there are program products that allow MVS to share DASD without use of R/R, but you are safer assuming that these packages are either not installed or are not turned on. Nothing is lost if virtual R/R is available; nothing gained, if not.
Regards, Richard Schuh -----Original Message----- From: VM/ESA and z/VM Discussions [mailto:[EMAIL PROTECTED] On Behalf Of Stephen Frazier Sent: Tuesday, January 31, 2006 10:36 AM To: [email protected] Subject: Re: MDISK versus LINK If you want to use reserve/release on the disk you must have all systems link to the same MDISK with MWV on the statement. That is the way you have it now. If you change it to have a different MDISK statement for each guest then reserve/release will not work. I don't know if z/OS uses reserve/release to serialize access to dasd or if it uses something else. You are doing it right now. If you make the change I can not guarantee that it will fail. :) [EMAIL PROTECTED] wrote: > I have a situation where multiple z/OS guests need to share DASD. In the > past I have used a userid as a disk holder with MDISKs using DEVNO and MWV. > The guests would then LINK to the MDISKs using MW. It has been suggested > that I eliminate the disk holder userid and use MDISK statements only. Each > guest would then have an MDISK for the same address. For example, > MDISK D000 3390 DEVNO D000 MWV > > Does anyone know if there is any advantage or disadvantage to one way over > the other? -- Stephen Frazier Information Technology Unit Oklahoma Department of Corrections 3400 Martin Luther King Oklahoma City, Ok, 73111-4298 Tel.: (405) 425-2549 Fax: (405) 425-2554 Pager: (405) 690-1828 email: stevef%doc.state.ok.us
