Hmmm. I don't know the history, but can imagine some problems. 1) VOLSER=11111 has n minidisks, defined in CP Object directory. 2) Now imagine that the disk is taken offline, perhaps for some DASD service. 3) And the CP Object directory is updated, re-allocating those minidisks to a new VOLSER=222222 and restored from tape. 4) Now whatever was wrong with access to VOLSER=111111 is fixed and it is brought back online.
The VTOC on 111111 reflects the old minidisks and their locations, while the CP Object directory reflects the valid locations. Confusion abounds (likely because someone was not told what ensued - how good are YOUR communications?). My questions are, what is the problem and what are you trying to solve/improve? Most questions are inspired by something that happened. What happened in this case? Mike Walter Hewitt Associates Any opinions expressed herein are mine alone and do not necessarily represent the opinions or policies of Hewitt Associates. "McKown, John" <[EMAIL PROTECTED]> Sent by: "The IBM z/VM Operating System" <IBMVM@LISTSERV.UARK.EDU> 03/15/2007 09:42 AM Please respond to "The IBM z/VM Operating System" <IBMVM@LISTSERV.UARK.EDU> To IBMVM@LISTSERV.UARK.EDU cc Subject Historical curiousity question. This is not important, but I just have to ask this. Does anybody know why the original designers of VM did not do something for "minidisks" akin to a OS/360 VTOC? Actually, it would be more akin to a "partition table" on a PC disk. It just seems that it would be easier to maintain if there was "something" on the physical disk which contained information about the minidisks on it. Perhaps with information such as: start cylinder, end cylinder, owning guest, read password, etc. CP owned volumes have an "allocation map", this seems to me to be an extention of that concept. Just curious. -- John McKown Senior Systems Programmer HealthMarkets Keeping the Promise of Affordable Coverage Administrative Services Group Information Technology The information contained in this e-mail message may be privileged and/or confidential. It is for intended addressee(s) only. If you are not the intended recipient, you are hereby notified that any disclosure, reproduction, distribution or other use of this communication is strictly prohibited and could, in certain circumstances, be a criminal offense. If you have received this e-mail in error, please notify the sender by reply and delete this message without copying or disclosing it. The information contained in this e-mail and any accompanying documents may contain information that is confidential or otherwise protected from disclosure. If you are not the intended recipient of this message, or if this message has been addressed to you in error, please immediately alert the sender by reply e-mail and then delete this message, including any attachments. Any dissemination, distribution or other use of the contents of this message by anyone other than the intended recipient is strictly prohibited.
