Google Groups no longer supports new Usenet posts or subscriptions. Historical content remains viewable.
Dismiss

z/VM CMS and z/Linux

33 views
Skip to first unread message

Raymond Noal

unread,
Sep 1, 2005, 4:00:01 PM9/1/05
to

Dear List,

Is there any way to prepare a z/VM mini-disk for intended use by a Linux virtual machine beforehand? Is there a CMS equivalent for the Linux DASDFMT and MAKEFS commands?

TIA

HITACHI
 DATA SYSTEMS

Raymond E. Noal

Lab Manager, San Diego Facility

Office: (858) 537 - 3268

Cell:   (858) 248 - 1172

Paul Hanrahan

unread,
Sep 1, 2005, 9:45:09 PM9/1/05
to
Why not just run linux on vmware ?

Rich Smrcina

unread,
Sep 1, 2005, 9:55:53 PM9/1/05
to
Because it's not zSeries.

Paul Hanrahan wrote:
> Why not just run linux on vmware ?
>


--
Rich Smrcina
VM Assist, Inc.
Main: (262)392-2026
Cell: (414)491-6001
Ans Service: (360)715-2467
rich.smrcina at vmassist.com

Catch the WAVV! http://www.wavv.org
WAVV 2006 - Chattanooga, TN - April 7-11, 2006

Paul Hanrahan

unread,
Sep 1, 2005, 11:32:50 PM9/1/05
to
And ??????

-----Original Message-----
From: VM/ESA and z/VM Discussions [mailto:VME...@LISTSERV.UARK.EDU] On

David Boyes

unread,
Sep 2, 2005, 10:10:27 AM9/2/05
to

>Why not just run linux on vmware ?

Because it's not the right answer for every problem, and it doesn't run on
zSeries.

>Is there any way to prepare a z/VM mini-disk for intended use by a Linux
virtual machine beforehand? Is there a CMS
>equivalent for the Linux DASDFMT and MAKEFS commands?

If you are going to use the DIAG driver (currently limited to 31-bit) you
can use CMS FORMAT and RESERVE to do the basic formatting, but that doesn't
help with 64-bit or non-DIAG I/O.

I suppose it wouldn't be too hard to write something like SWAPGEN to dump
the right partition and fs blocking onto a minidisk, but I don't know that
anyone has done so yet.

Bruce Hayden

unread,
Sep 2, 2005, 11:01:36 AM9/2/05
to
I'm surprised that Rob hasn't jumped in yet and mentioned his CMS2CDL package on the VM download page (http://www.vm.ibm.com/download/packages/ and look for it.)  I've used it for awhile and it works great.  It does the equivalent of a dasdfmt and fdasd -a command and then you can put the disk in an LVM or put a filesystem on it.
--
Bruce Hayden
IBM Global Services zSeries Linux
Endicott, NY

David Boyes

unread,
Sep 2, 2005, 12:21:52 PM9/2/05
to
> Of course, you can use a 31-bit Linux to do your formatting
> and then use a 64-bit Linux for the actual server.

I think he was looking for a way OUTSIDE of Linux to do the format and
partitioning.

Adam Thornton

unread,
Sep 2, 2005, 12:44:05 PM9/2/05
to
On Sep 2, 2005, at 7:10 AM, David Boyes wrote:
>
> I suppose it wouldn't be too hard to write something like SWAPGEN
> to dump
> the right partition and fs blocking onto a minidisk, but I don't
> know that
> anyone has done so yet.
>
Hazy memory suggests that there was briefly such a tool back in 2.2
days, right as Linux on 390 was getting off the ground. Maybe Rob
van der Heij wrote it? It was basically mke2fs for a minidisk.

Anyway, with that plus e2, you could do whatever you wanted in terms
of creation of Linux ext2 filesystems from CMS (well, you would also
want a zipl-equivalent). Not sure exactly what that would buy you--I
guess, lay down a filesystem and populate it without ever having to
boot Linux--but I don't think it'd be very hard.

Adam

Rob van der Heij

unread,
Sep 3, 2005, 12:10:02 AM9/3/05
to
On 9/2/05, Adam Thornton <atho...@sinenomine.net> wrote:

> Hazy memory suggests that there was briefly such a tool back in 2.2
> days, right as Linux on 390 was getting off the ground. Maybe Rob
> van der Heij wrote it? It was basically mke2fs for a minidisk.

Wrote it back then, but it took longer to publish it. As Bruce points
out, CMS2CDL is on the VM Download pages. It takes a CMS-formatted
disk and makes it into a CDL disk with a single partition using all
space (fdasd -a). All you need is make the filesystem of your choice
on it, but YaST is willing to do so during install.
It was very helpful when we had the FORMAT hack that came with the RVA
to use snapshot under the covers.

With SLES8 the installer got upset if you had not formatted the disks
like this upfront, I think that is fixed in SLES9.

Obviously the memory usage of a Linux machine running dasdfmt is much
larger than that of a CMS user doing FORMAT...

:soapbox.
Actually, I created this after dasdfmt was fixed to remove the option
to format only part of the disk. Until then we would CMS FORMAT and
then dasdfmt only cyl0. The option was removed because the support
teams had so many calls from customers with disks that were not
completely formatted. I still believe the cause was a race condition
in the code that occasionally missed a track while formatting. That's
why one of the Redbooks comes with the silly recommendation to run CMS
FORMAT before running dasdfmt (since all you need is modify cyl0, so
missing some tracks does not hurt).
:esoapbox.

Rob

--
Rob van der Heij rvdheij @ gmail.com

Adam Thornton

unread,
Sep 3, 2005, 2:00:03 AM9/3/05
to
On Sep 2, 2005, at 9:10 PM, Rob van der Heij wrote:
> That's
> why one of the Redbooks comes with the silly recommendation to run CMS
> FORMAT before running dasdfmt (since all you need is modify cyl0, so
> missing some tracks does not hurt).

Hey, I still do this. Superstitious? Probably. I should start
using CMS2CDL.

Adam

0 new messages