Re: creating DASD

Ivan,

I forgot that you can logon to CP / VM, without having CMS running ;)
... and that you could do an IPL command from CP.  ...

Even though I've done an IPL  many times ;)

 (I.e. dropped to a CP prompt for various reasons .. redefining STOR size ..etc)

Mike

On 8/7/10, Ivan Warren <[email protected]> wrote:
> 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.
>