If you get an I/O error paging out or paging in, I would suspect that z/VM would abend. I would think that by having the paging volumes on both, you would be increasing your odds of a crash by 2x (1 for each ds8000 that could fail).
You don't have to replicate your page volumes, but you would want to have the others sitting on DS2 initialized and ready to go. You can use the same volsers, but then you'd probably want to us different system config files and the Offline_at_IPL statement depending on if you IPLd off of DS1 or off of DS2 (VM can IPL with a different system config file name in the load parm or from the SAPL screen). Or you can get really fancy and not go down at all and Hyperswap between ds8000 boxes. That's a whole 'nother ballgame though. Marcy "This message may contain confidential and/or privileged information. If you are not the addressee or authorized to receive this for the addressee, you must not use, copy, disclose, or take any action based on this message or any information herein. If you have received this message in error, please advise the sender immediately by reply e-mail and delete this message. Thank you for your cooperation." ________________________________ From: The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] On Behalf Of Florian Bilek Sent: Monday, August 31, 2009 1:24 AM To: IBMVM@LISTSERV.UARK.EDU Subject: [IBMVM] Reaction of z/VM when losing a page dataset Dear all, I am wondering about the reaction of z/VM in case it would lose one or two page datasets. The reason is that I have a configuration with two DS-8000 where the page datasets are spread all over those two machines. DS-1 has the sysres, spool, and some page datasets and DS-2 it has additional page datasets. The system disks are mirrored by PPRC. So in case DS-1 will become unavailable I can continue on DS-2. This will be disruptive of course. Since the page datasets consume a lot of addresses we don't mirror them. In case DS-2 would become unavailable, would z/VM then crash? Would it be better to have all CPOwned volumes on one DS-8000 or can my current configuration remain as it is? Any opinion is appreciated very much. Furthermore I would like to ask if the new version of z/VM will allow emptying a page dataset in order to drain it and detach it without IPL. I just experienced that a drain of that volume not really helps. Thank you very much in advance. Kind regards, Fox
