We let z/VM sense all volumes and z/OS owns the IODF and IOCDS's. We've had zero issues with z/VM touching volumes it isn't supposed to.
Jerry Whitteridge Lead Systems Programmer Safeway Inc. 925 951 4184 If you feel in control you just aren't going fast enough. -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Ron MacRae Sent: Wednesday, May 16, 2012 1:04 PM To: [email protected] Subject: Co-existance of z/OS and z/VM on same DASD farm Hi all, We are currently an exclusively z/OS site with multiple LPARs sharing a single IOCDS and DASD farm. We are about to install z/VM in a new LPAR and I'm worried about both OSs sharing the same DASD farm. They will not be sharing at the volume level. I've read through the install doc and it all seems fine, you tell the install process 6 or 9 unit adresses and it goes and loads stuff onto them and then you IPL. There is no mention of modifying other volumes, however there are include and exclude unit address lists that you can specify to define what z/VM will try to look at, which presumably you can't get at until after the basic install and IPL. Also z/VM can issue sense commands to determine what devices are out there. The reason I'm worried is that in a previous life, over 30 years ago, my previous company attempted to do the same between an VM system and a DOS/VSE system. This was a long time ago on a real machine in pre LPAR days. When they brought up VM for the first time it objected to the VSE VTOCs it found and rewrote them as OS VTOCs and we lost the whole DASD farm. Management were not best pleased. I wasn't directly involved at that time so I'm not 100% sure of my facts here and perhaps the guys who did this did something wrong, however my worry still remains. My question is - Do we have to isolate z/VM from the z/OS volumes or will z/VM play nice and leave stuff alone? I just want to double check that VM will only touch the 6 volumes it is given at install time. Regards, Ron MacRae. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN "Email Firewall" made the following annotations. ------------------------------------------------------------------------------ Warning: All e-mail sent to this address will be received by the corporate e-mail system, and is subject to archival and review by someone other than the recipient. This e-mail may contain proprietary information and is intended only for the use of the intended recipient(s). If the reader of this message is not the intended recipient(s), you are notified that you have received this message in error and that any review, dissemination, distribution or copying of this message is strictly prohibited. If you have received this message in error, please notify the sender immediately. ============================================================================== ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
