Ah - well DEVNO isn't supported in the referenced report ;-) (an in house thing from long ago)
I didn't mean to state my 'rules' as law -- I always hate it when others do that :-) More like "Scott's Rules"... Most of my reasons for wanting to see specific cylinders in the directory revolve around avoiding the need for Q DASD DETAILS... whether remote or not. One example is someone who thought the volumes they picked were 3390-9 and but were 3390-54. They coded the MDISK statements 1 to END (from habit) - told the Linux folks they were ready - and now we have a very bloated Linux guest and can't just move the minidisk to another volume (like we could if they had specified the size of 10016). Mostly - specifying the size just avoids confusion and gives an immediate view of the number of cylinders the MDISK requires. END is ambiguous and requires knowledge of the # of cylinders defined on the volume. Avoiding ambiguity goes a long way to eliminating errors... <shrug> YMMV I consider it a 'best practice' and list it as such for customers.. The exception are 'disk holder' users - like those that define all the volumes on the system as 0 END for the purposes of physical backup, etc. Then END makes sense because you want the whole volume defined regardless of size and it's an 'overlay' disk. Scott Rohling On Mon, Jun 21, 2010 at 1:18 PM, Schuh, Richard <rsc...@visa.com> wrote: > What do you do for your reports if an mdisk is defined by DEVNO instead > of volser? You have remote access to the directory but cannot get the output > from QUERY DASD DETAILS? > > You have your preferences, which you state as though they are an absolute > law. I have mine which are different from yours, so I guess I am breaking > the law :-). I hope the offense is not a felony. If I am ever in a position > where I have to report on DASD usage by cylinder from a remote location that > has access to the directory but not to the system, I might change. Until > then, I see no compelling reason why I should switch. > > > Regards, > Richard Schuh > > > > > ------------------------------ > *From:* The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] *On > Behalf Of *Scott Rohling > *Sent:* Monday, June 21, 2010 10:53 AM > > *To:* IBMVM@LISTSERV.UARK.EDU > *Subject:* Re: what is a 'full pack' minidisk? > > I'm NOT advocating the use of END when defining MDISKs! One of the first > things I beg my customers to do is stop using END and use the number of > cylinders on all MDISK statements. I concur that it's lazy and creates > extra work and confusion. Also makes creating DASD usage reports out of a > directory from a remote system impossible. > > My original post was about how to refer to a minidisk that's defined from > 1-END -- because that language fits all sizes. Referring to it and > actually defining it are two different things. Always use the number of > cylinders when defining an MDISK. Never use END. On a DEFINE MDISK > command - go ahead and use END -- but NOT in the directory. > > Scott Rohling > > On Mon, Jun 21, 2010 at 9:59 AM, Schuh, Richard <rsc...@visa.com> wrote: > >> On the other hand, it is possible for 3390-xx devices to be most any size >> that you want. The -03, -06 etc. designations are almost meaningless. You >> are not required to define (in the CU) a multiple of 3339 for the disk >> sizes. In this environment, 0-END is the way to define a full-pack minidisk >> regardless of the number of cylinders. The other way would be by DEVNO, iff >> you can count on the hardware people never changing the address. Here, the >> hardware people have changed the addresses of disks and have redefined >> capacities upward, but they have never changed a volser of one of the VM >> packs or created a duplicate of one that I care about; 0-END is best for me. >> >> I agree with the idea that a minidisk defined from 1-end is just a >> minidisk and the full-pack designation is a special case, unique unto >> itself. Personally, I have never seen the need for a term for an mdisk >> defined as 1-end, where "end" is either the word "END" or a number that is >> the equal to highest cylinder of the disk. Aside from being lazy, not >> wanting to periodically (after every h/w activity that includes messing with >> the dasd controllers) have to enter QUERY DASD DETAILS for every disk that I >> want protected by an MDISK that covers the entire disk, prefer the use of >> END instead of 3339, 10016 or whatever the ending cylinder number is. As an >> aside, I have seen some (physical) disks defined as small as 100 cylinders. >> >> >> Regards, >> Richard Schuh >> >> >> >> > -----Original Message----- >> > From: The IBM z/VM Operating System >> > [mailto:ib...@listserv.uark.edu] On Behalf Of Brian Nielsen >> > Sent: Monday, June 21, 2010 7:59 AM >> > To: IBMVM@LISTSERV.UARK.EDU >> > Subject: Re: what is a 'full pack' minidisk? >> > >> > I second what Jim Hughes said - essentially that if it >> > doesn't include = >> > >> > cylinder 0 it's just a "minidisk", no matter what the size. >> > >> > Personally, and as discussed here by others in the distant >> > past, I prefer= >> > >> > to not give out the last cylinder of a real volume in order >> > to make it = >> > >> > much easier to copy a 1st level volume for 2nd level testing. >> > Doing this= >> > >> > is just an extention of the same logic that leaves the last >> > cylinder of = >> > >> > the system volumes empty by design (as requested of IBM by >> > user groups). >> > >> > So now you need a term for a 1 to (END-1) minidisk.... :) >> > >> > On a related note, I don't like using "END" in the first >> > place because = >> > >> > it's not obvious how big it is unless you know the size of >> > the volume. = >> > >> > It's an unneeded obfuscation. >> > >> > Brian Nielsen >> > >> > >> > >> > >> > On Fri, 18 Jun 2010 16:45:54 -0600, Scott Rohling >> > <scott.rohl...@gmail.com> wrote: >> > >> > >I like that - it does imply 'almost'.. but now I'm going >> > for '12end'. >> > >We'll see if it lasts through the weekend ;-) Tot ziens! >> > > >> > >Scott Rohling >> > > >> > >On Fri, Jun 18, 2010 at 4:33 PM, Rob van der Heij >> > <rvdh...@gmail.com> = >> > >> > wrote: >> > > >> > >> On Fri, Jun 18, 2010 at 11:26 PM, Scott Rohling >> > <scott.rohl...@gmail.com> >> > >> wrote: >> > >> > Ok -- darn it. "a 1 to END minidisk" just doesn't >> > have the same = >> > >> > ring >> > >> to >> > >> > it as 'full pack'. And it's another syllable to mumble.. ;-) >> > >> >> > >> Care for my "pseudo full-pack" terminology maybe? (sounds more >> > >> official than "almost full-pack") >> > >> >> > > >> > >> > >
