I agree. The writer is wrong. There is plenty of code, even with z/OS
V1.4, which cannot be 'swapped into place', on a running system.
..thanks

Steve Gentry wrote:
>
> The writer made the comment that :
> <snip>
>
> Well, IBM (NYSE: IBM - news) mainframes as old as the original System 370, which 
> debuted in 1970, had
> the ability to create what are called virtual machines, which allow one
> version of the operating system to keep running while a kind of duplicate
> copy running on the same physical machine is upgraded. Once a fix is made
> to code, the patched version of the OS can be swapped into place for the
> running version, all without taking down the system.
>
> </snip>
>
> Further . . .
>
> "Once a fix is made to the code, the patched version of the OS can be
> swapped into place . . . without taking down the system"
>
> I've been a sys.prog. for about 20 years, 15 of those in VM and I don't
> know of any feature that will let a sys prog do this!  If so, I've spent a
> lot of late nights and weekends upgradeing when I could have done it
> during the week. In reality, no you do not have to power the box off, but
> you do have to cycle VM or VSE.  I'm not sure about z/OS, but since the
> author mentions "virtual machines" aka VM, in my opinion he is wrong.  Now
> don't misunderstand me, I'm for VM getting all the "accurate" press it can
> get.  However, if some unknowing decision maker takes this and runs with
> it, VM could be set up for some bad press.  As I understand the article,
> he is trying to imply that VM never has to be taken down, cycled, IPL'd,
> booted, what ever term you want to use, to bring new OS code in.  I should
> mentioned one exception that I know of.  VSE had/has a mechanism to bring
> patched code in.  I don't remember the exact process anymore, but it was
> used in emergency situations only.  I would never apply a list of PTF's to
> VSE and bring it on line via this method. VM may have a similar function.
> If so I've never used it.  Heck, VM hardly ever breaks. (my plug for VM).
> But in this case, the method of bring in patched code is not unique to VM.
> Sort of off thread.  At one site I worked at, me and another sys.prog
> convinced the Op. Manager that we had done a "Shadow IPL", i.e, bring new
> OS code, more than one module, into use while the machine was still
> running.  He believed us for about 5 minutes.
> Steve G
>
> Phil Payne <[EMAIL PROTECTED]>
> Sent by: Linux on 390 Port <[EMAIL PROTECTED]>
> 03/17/2003 03:45 PM
> Please respond to Linux on 390 Port
>
>         To:     [EMAIL PROTECTED]
>         cc:
>         Subject:        Interesting perspective
>
> http://story.news.yahoo.com/news?tmpl=story2&cid=75&ncid=738&e=9&u=/nf/20030317/tc_nf/21020
>
> --
>   Phil Payne
>   http://www.isham-research.com
>   +44 7785 302 803
>   +49 173 6242039

Reply via email to