Re: creating DASD

Mike Stramba wrote:
> Ivan,
> 
>> CP IPL <CUU> STOP
>> .. Do the Dial
>> CP BEGIN
> 
> Where do  the CP IPL <cuu> STOP  / CP BEGIN commands get issued from ?
> 

Those commands should be issued from the virtual machine that is setup 
to run MVS.

The <CUU> would be the virtual address within your virtual machine of 
your OS system residence volume.

You do not need to IPL CMS or have a 191 minidisk (but you can). For all 
intents and purposes, MVS 3.8J cannot be started automatically in VM/370 
*IF* you intend to use a DIALed device for the MVS system console - You 
need to issue the previously mentioned sequence of commands manually 
directly from the virtual machine.

However, it can be automated if you use *DEDICATED* devices (Either 
using the CP ATTACH command (but this requires you virtual machine to be 
class B - which isn't necessarily a Good Thing (tm)) or by using DEDICAT 
statements in your CP Directory for that virtual machine (watch out : 
the order between Virtual and Real devices are permuted between 'CP 
ATTACH' and the 'DEDICAT' CP Directory statement[1].

Setting up a virtual machine to run a guest operating system (besides 
CMS that is) is not very difficult - but it's not trivial either. It 
requires some careful planning in both how VM is set up, how the virtual 
machine is configured and how the real underlying system (in this case 
hercules) is constructed -  but most of all, it helps a lot when you 
have a good grasp of how system virtualization works.

--Ivan

[1] which makes sense.. With the CP "ATTACH" command, you are attaching 
a REAL device to a Virtual Address in a virtual machine. With the 
"DEDICAT" statement, you are defining a Virtual Device - with has a 
corresponding Real Device Address.