Mainframe, MVS and zOS Discussion

Hi,

I have joined a new company and the setup here is very different than what it was in my last company. When I login to my testing environment on mainframes, they call it as TSOD and I use my ID/password to login. I create my test files here. Now when I login to production TSOP, I need to logoff from test log in to mainframes. Questions I have are

1. Why I need to log-off from development to login to production? It was never required in my previous company.
2. Why the file I create in test is visible in production? In my previous company they never showed up like that. We used to NDM a file to our test region to get the data from a production file to test for testing.

Could someone please guide why this happen and if there is I can read about such things more.

Why I need to log-off from development to login to production? It was never required in my previous company.

different company , different setup, different standards

why ask on a forum, ask Your colleagues

having a tso session open on <prod> and <devel> at the same time might lead to unwanted consequences

the wrong command in the wrong emulator session for example... seen it too many timed

As you have learned, there is a LOT of customization that can be done to z/OS. Shared logons between LPARs is one and shared disk (and/or tape) drives between LPARs is another. There are advantages and disadvantages to each approach, which is why sites are not all standardized. I don't know of any single source to read about such customization; if you're really wanting to learn a bit start with the MVS Initialization and Tuning Reference manual that is available on the IBM web site.

Thanks.

What I want to know is that when I am able to see the files on both regions that is Test and Production, does that mean that it is a single mainframe? And that means that it has got only one processor which is in use in both test and production?

does that mean that it is a single mainframe?

no... only that the dasd are shared

read and meditate on
http://www.redbooks.ibm.com/abstracts/s ... .html?Open

does that mean that it is a single mainframe? And that means that it has got only one processor which is in use in both test and production?

Your thinking is quite limited. The current IBM mainframe, the z14, can have up to 170 processors (cores to a Windows / Linux user), which can be split into general processors (CP), Linux processors (IFL), specialty engines (zIIP), coupling facility engines (ICF) and System Assist Processors (SAP) in various configurations.

A z14 supports up to 85 LPARs (logical partitions), which is -- most likely -- what you are calling "test" and "production". Processors can be assigned to a single LPAR or processors can be shared between LPARs. Each LPAR, for the most part, acts as a stand-alone machine. Disk and tape drives can be isolated to a single LPAR or shared among various LPARs. Furthermore, these machines can run with knowledge of the other machines in their network (which can be quite large -- GDPS or Geographically Dispersed Parallel Sysplex allows MILES between machines) so there may be many ways the system could be set up.

You seriously need to talk to your site support group to find out the details about your site, since each site is set up uniquely based upon the company's requirements.

Thanks for you reply. I understand that there are many ways to do such set-up. I am just trying to understand that if this happens: 2. Why the file I create in test is visible in production?

Or you mean to say that there can be many differnt configuration which can show such behavior and there is not always similar setup for this behavior?

Why the file I create in test is visible in production?

see my previous reply and READ the manual I pointed You to

2. Why the file I create in test is visible in production?

As you have already been told, your new organization is using shared DASD. At my site, for example, we use shared DASD so every data set is visible to every LPAR (we have production, database, and test LPARs).

Thanks all.

Hi Enrico,

I am reading the document you have shared and I might have some follow up question. Will post them.