management: Become a Mainframe Rembrandt - Creating a Picture of your Mainframe Configuration
In this article, we look at the difficulties in creating comprehensive,
up-to-date Mainframe configuration information, what this means to your organisation,
and some tools that can help.
What do your Mainframe systems look like? You could answer that they're
a couple of black refrigerator sized boxes. Or you could go into more
detail, like "three z/OS LPARs in a Parallel Sysplex, each running
one IMS, one DB2 and a couple of CICS regions".
Keep going into more detail, and you're quickly going to run out of information.
For example, what DB2 tables do you have, and what applications use them?
Technical staff like your Systems Programmers, Applications Programmers
and DBAs will have some of this information, but their knowledge will
be focused on their area of speciality.
So it's no surprise that most organisations don't have a comprehensive, complete,
up-to-date picture of their Mainframe configuration. But is this important?
And if it is, how do you create one?
The Difficulty in Painting your Mainframe Picture
In years past, the Mainframe picture was quite simple. Take the example
on the right of an IMS region:
A single IMS subsystem would have pre-defined transactions, programs
and databases. The relationship between these was also pre-defined. IMS
transactions were generally accessed via 3270 terminals or batch.
Compare this with a more modern IMS subsystem below:
It's a lot more complicated isn't it? Different IMS region types, Websphere
MQ, IMS Connect, DB2 and the IMSPlex infrastructure all complicate your picture.
Mainframes also have a different problem to smaller distributed platforms -
the number of resources. For example, DB2 subsystems can have hundreds of thousands
of tables, views, tablespaces and indexes.
Finding out all this information for all of your Mainframe systems (not just
IMS) is a Herculean task. You may already have some, but is it complete, or
up-to-date? Many different groups in your organisation may have some of the
picture, but not all of it, and not all the detail you need.
But what is even harder is the task of determining the relationships between
them. What applications use a particular DB2 table? Do any CICS transactions
call IMS transactions?
Do You Need a Mainframe Picture?
So is it such a big deal if you don't have this information? In a word - yes.
Configuration information is critical for:
Your Mainframe Canvas
So you're about to start accumulating data about your Mainframe configuration.
In other words, you're going to create a Configuration Management Database (CMDB).
You can certainly create your own database application to do all this, but most
organisations will use a commercial product. Favourites for z/OS configuration
- To store your configuration information
- An application for you to add, delete and maintain the information.
- A way to present your information.
- BMC Atrium CMDB
- IBM Tivoli Change and Configuration Management Database (CCMDB)
For Mainframe users, these may appear more attractive to other CMDB products
as they are able to connect to other Mainframe products to automatically receive
Painting Your Mainframe Picture
Now we get down to your biggest problem - how to get your configuration data,
and keep it up-to-date. The good new is that there are tools on the market to
make your job easier. We've already talked about how CMDB products can obtain
configuration data from other products. For example:
- IBM Tivoli CCMDB can get data from Tivoli products such as Netview and Tivoli
Business Systems Manager. It can also discover z/OS resources using a Discovery
Library Adapter (DLA) for z/OS.
- BMC Discovery for z/OS automatically populates CMDB products with discovered
- The upcoming CICS TS 4.1 provides a facility to send CICS configuration
data to a CMDB.
These products will automatically discovery most of your z/OS components. They
also provide some (but not all) of your relationship information, like which
DB2 databases belong to which DB2 subsystems. Using these products regularly
ensures you have up-to-date information.
However these tools won't give you everything. You're not going to get away
from the fact that a lot of your information needs to be entered and updated
manually, and often. Convincing your staff to do this is going to be as hard
as getting your teenage children to cleanup their rooms.
One interesting software product that may help here is Novell's myCMDB product.
This uses social networking technology similar to Facebook to make it easier
(and more fun) for teams to maintain configuration information.
Managing Mainframe infrastructure is a complex task. This isn't going to get
any easier as Mainframe applications talk more with other applications - both
on and off the Mainframe. Having accurate, comprehensive, up-to-date information
on your Mainframe configuration is a big step to keeping this under control.
CMDBs and other associated tools go a long way to making this happen.