May Mainframe Madness

For all the posts I've had of late about free educational and technical materials, I've been remiss to mention what my own company has been up to.

This month CA is running an event it describes as the world's largest virtual mainframe trade show: CA May Mainframe Madness 2012. By registering here, you can access webcasts, live chats and "on demand" presentations hosted by technical experts from across the mainframe world.

Here are some upcoming webcasts:

• Thursday, May 17, 10 a.m. EDT: Sheryl Larsen
        - DB2 9 and 10 SQL: Index and Optimization Enhancements
• Wednesday, May 23, 10 a.m. EDT: Craig Mullins and Steve Crocker
         - Getting to DB2 10 for z/OS

Here are some presentations:

• On Demand – Craig Mullins
         - DB2 Top 10 Lists Part 1
         - DB2 Top 10 Lists Part 2
• On Demand – Steen Rasmussen
       - Tips for Better DB2 for z/OS Performance
       - Do You Really Want NOT to LOG?
       - The DB2 10 catalog – A Revolution

And on Tuesday, May 29 at 1 p.m. EDT, there's a live chat roundtable with Sheryl Larsen, Steen Rasmussen, Scott Jessee and Dave Schipper. The moderator is none other than yours truly.

Once you've registered, you'll get a better idea of the virtual trade show format (you can also view these photos: Image 1, Image 2, Image 3, Image 4, Image 5). Stop by the "Database Management booth" in the "exhibit hall" to ask questions, or check out the "House Of Mainframe lounge" to network with peers, check for messages, join a group or sign up for a chat.

Learning DB2 for z/OS

This recent post about the free IDUG workshop prompted a reader from India to ask about the availability of such education in his region. Fortunately, just having Internet access opens up a world of inexpensive  DB2 for z/OS resources.

For instance, IBM manuals: Whenever I need to get started with something new, the DB2 for z/OS manuals are my first stop.

Then there are the DB2 for z/OS certification guides:

• DB2 9 for z/OS Database Administration: Certification Study Guide
• DB2 9 System Administration for z/OS: Certification Study Guide: Exam 737
• DB2 10 for z/OS Database Administration: Certification Study Guide

 There's also this IBM book that makes the case for upgrading to DB2 10.

 And don't forget about DB2 blogs.

Finally, I recommend this IBM presentation by Surekha Parekh, Willie Favero and Susan Visser: "Staying in Touch with the World of DB2 for z/OS." It greatly expounds on my brief blog list, covering an array of DB2 for z/OS collaborative groups.

More on zEnterprise

As a follow-on to last week's post about IT pros in the LUW space who need to educate themselves on the mainframe and z/OS, here's a quick list of informational and technical resources.

As a starting point, visit IBM's zEnterprise home page. Here you'll find an overview of mainframe servers and other hardware.

The Linux on IBM System z homepage provides an overview of the benefits of using Linux in mainframe environments.

Here are some zEnterprise IBM Redbooks that have been updated in the past month:

IBM zEnterprise 196 Technical Guide

IBM zEnterprise 114 Technical Guide

IBM zEnterprise Unified Resource Manager: Building an Ensemble

A Structured Approach to Assessing Heterogenous Workload Deployment to the IBM zEnterprise System

Finally, here are some of my previous posts related to the topic of zEnterprise:

• IBM Introduces IDAA to Speed Analytics
• The Significance of the IBM zEnterprise System
• The Mainframe and Information Management
• The System of Systems

Hopefully you find this information helpful. Please share your own sources of information in Comments.

The Ambidextrous IT Workforce

Over the years IT pros working on distributed platforms (Linux, UNIX, Windows) have often asked me how they can learn more about the mainframe and z/OS. When it comes to broadening one's horizons, I think mainframe DBAs have an easier time picking up UNIX or Linux (and in some cases Oracle and SQL Server) to support DB2 UDB. Being able to download tools, particularly Linux, is the best way to get started with something new.

Still, I'm seeing more and more people from the Linux world who find themselves needing to learn about the mainframe. This trend really got rolling with last year's introduction of the z/196, and with the increasing use of zBX blades running zLinux as well as z/OS on z/196 and z/114, I think the next generation of IT pros will only continue to find themselves more involved with the mainframe.

If you're an "ambidextrous" worker moving from LUW environments to z/OS, make it a point to bookmark the IBM z/OS basic skills information center. You'll find tons of material on mainframe and z/OS concepts. It'd also be nice to hear about your experiences and how you compare the challenges of managing z/OS and non-Z/OS system, so please share in Comments.

 

 

 

Updates to Redbooks on DB2 10 for z/OS

I've written quite a bit about both IBM DB2 for z/OS manuals and IBM DB2 Redbooks. I generally use the manuals to educate myself about DB2 for z/OS features. When I'm looking for more in-depth details on different areas of practice within DB2, I often turn to Redbooks.

As with manuals, Redbooks are updated on a regular basis. Here's a quick list of DB2 Redbooks that I've read and used. All have been published or updated within the past year. The first two listings include links to previous blog entries I've written about these publications.

• "DB2 10 for z/OS: Configuring SSL for Secure Client-Server Communications" (published: Oct. 11, 2011; last update: Dec. 5, 2011; previous post: Getting Started with SSL)
• "Security Functions of IBM DB2 10 for z/OS" (published: Sept. 2, 2011; last update: Sept. 14, 2011; previous post: Roles and Trusted Context)
• "DB2 10 for z/OS Performance Topics" (published: June 21, 2011; last update: Dec. 6, 2011)
• "DB2 10 for z/OS Technical Overview" (published: Dec. 30, 2010; last update: Dec. 6, 2011)
• "Managing IBM DB2 10 for z/OS Using the IBM DB2 Administration Tool for z/OS Version 10" (published: April 22, 2011)
• "Extremely pureXML in DB2 10 for z/OS" (published: Jan. 28, 2011)

DB2 10 Audit Policy

The DB2 trace facility provides a method to collect monitoring, auditing and performance information about your data, application and system. DB2 10 introduces the capability to define an audit policy to generate trace records based on an audit category.

DB2 audit policies are defined by inserting rows into the SYSIBM.SYSAUDITPOLICIES table. Each policy is specific to one of these categories:

CHECKING:         Logs audit access denied attempts as well as external security authentication failures.

VALIDATE:           Logs instances when a trusted connection is established or when a new user is using the connection.

OBJMAINT:         Logs instances when a table is altered or dropped. This includes cloned tables and implicitly created tables for XML columns.

EXECUTE            Logs instances when the given object schema, name and type is accessed during the first operation performed by each unit of work. Also records bind time information about SQL statements that include tables identified by object schema, name and type.

CONTEXT:           Audits all utilities.

SECMAINT:         Audits grant, revoke, create trusted context and alter trusted context.

SYSADMIN:         Logs instances of operations being performed using an administrative authority (install SYSADM, SYSADM and SYSCTRL; install SYSOPR and SYSOPR) to perform system administration tasks.

DBADMIN:          Logs instances of operations being performed using an administrative authority (system DBADM, DBADM, DBCTRL, SECADM, ACCESSCTRL, SQLADM, DBMAINT, PACKADM and DATAACCESS) to perform database administration tasks.

Once a policy is defined in SYSIBM.SYSAUDITPOLICIES, it can be activated by using the START TRACE command for an audit with the policy parameter AUDTPLCY(policyname). To learn more about audit policy and see examples, see the DB2 10 for z/OS Administration Guide.

 

 

 

 

Defining a DDF Location Alias

Recently I introduced the MODIFY DDF command in DB2 10 and explained how it can be used to STOP and START connections to support maintenance windows. MODIFY DDF can also be used to define DDF locations so you can manage subsets of data sharing members dynamically (online) without the need to stop and restart DDF or DB2. Applications can use the alias parameter in a non-data sharing environment to avoid application changes later when converting to a data sharing environment.

This example shows how you can add a new alias, set the port number then start the alias to allow applications to begin connecting.

-MOD DDF ALIAS(TROYDB) ADD
-MOD DDF ALIAS(TROYDB) PORT(5156)
-MOD DDF ALIAS(TROYDB) IPV4(141.202.65.11)
-MOD DDF ALIAS(TROYDB) START

Forgetting to start the alias or issuing the MODIFY ALIAS STOP comment results in this error:

Could not connect to TROYDB.
  Error creating SQL Model Connection connection to TROYDB.
           (Error: No start database command was issued. ErrorCode = -4499, SQLState = 08001.)
            No start database command was issued. ErrorCode = -4499, SQLState = 08001.
  Error creating JDBC Connection connection to TROYDB.
          (Error: No start database command was issued. ErrorCode = -4499, SQLState = 08001.)
           No start database command was issued. ErrorCode = -4499, SQLState = 08001

Using MODIFY DDF with the alias parameter provides some flexibility by separating the database name from the location name defined in job DSNJU003. You can then define member-specific IP addresses for the location alias created with MODIFY DDF. You can get information on what aliases are defined by using the DISPLAY DDF comment. Here's an example:

DSNL080I  !D10A DSNLTDDF DISPLAY DDF REPORT FOLLOWS:           
DSNL081I STATUS=STARTD                                         
DSNL082I LOCATION           LUNAME            GENERICLU        
DSNL083I D10APTIB           USILDA01.D10ADB2  -NONE            
DSNL084I TCPPORT=4276  SECPORT=4278  RESPORT=4277  IPNAME=-NONE
DSNL085I IPADDR=::141.202.65.11                                
DSNL086I SQL    DOMAIN=usazcp31.ca.com                         
DSNL087I ALIAS              PORT  SECPORT STATUS               
DSNL088I TROYDB             4276  4278    STARTD               
DSNL105I CURRENT DDF OPTIONS ARE:                              
DSNL106I PKGREL = COMMIT                                       
DSNL099I DSNLTDDF DISPLAY DDF REPORT COMPLETE

The capability to modify the alias and change the port numbers and/or the IPADDR without taking down DDF or DB2 is a great enhancement. You should look into how MODIFY DDF can help you better manage your application servers.

DB2 10 Data Sharing Fix Issued

IBM recently released a Red Alert for customers who are using data sharing and DB2 10 for z/OS.
Fortunately we don't see these very often. When they are issued they should be taken very seriously. From the alert:

"IBM has become aware of potential data loss when running data sharing under any mode of DB2 10 for z/OS.

"DB2 10 for z/OS takes advantage of a CFCC/XES performance enhancement by allowing repeated READ CASTOUT CLASS requests to the CF to utilize a restart token and retrieve from the queue where the previous read left off. A defect has been identified in this implementation of the enhanced READ CASTOUT CLASS in DB2 10 for z/OS."

The alert further states that APAR PM51655 should be applied to revert the DB2 10 behavior of the READ CASTOUT CLASS to the DB2 V9 (and prior releases) behavior.

Read more about this Red Alert and the recommended action here.
 

IBM Introduces IDAA to Speed Analytics

Not that long ago, running a large report typically took a few hours, and that was fine. But given the critical role that business intelligence now plays in making business decisions, time is a luxury.

Reading this explanation of BI, I was reminded of some of my work in the area of tuning decision support queries. These queries eventually ran against a separate copy of the data known as a data warehouse to avoid impacting the operational data.

As the need to run analytic queries against operational data becomes greater, the fact that these queries are often still long-running (and can provide unpredictable response times) becomes a bigger issue. To streamline the process, DBAs are asked to analyze and tune the SQL, which of course, besides being time-consuming for us, doesn't always produce favorable results anyway. And when companies don't get favorable results, they may look to other platforms to provide their analytics.

Last year, IBM is came out with IBM Smart Analytics Optimizer (ISAO) for DB2 for z/OS V1.1, which ran on z/Enterprise 196 with zBX hardware. Now just 15 months later, IBM has unveiled IBM DB2 Analytics Accelerator for z/OS V2.1. IDAA runs on IBM zEnterprise 196 or 114 with IBM Netezza 1000-3 hardware. Simply put, this solution is designed to provide faster response times for long-running, unpredictable queries. IBM also touts it as a cost-saver, because it's intended to save DBAs from implementing expensive SQL tuning efforts that can require new indexes or materialized query tables (MQTs).

Like the zIIP engines, the IDAA is a workload-optimized platform designed for special purpose processing. As such, you don't need to change your application to take advantage of it.

If you have the opportunity to work with IDAA, please post a comment so others can benefit from your experience.

Using the Display Database Command

DISPLAY DATABASE is one of the most useful and versatile commands in the DBA toolbox. It's used to  display information about the status of the database, table space and/or index space. It also displays who is using an object, any locks that are being held, any claimers and any pages in error.

However, it can be challenging viewing display database command results, because it's not obvious which columns are displayed and what they mean. To get the details, look up message ID DSNT397I in the DB2 10 for z/OS MESSAGES Guide.

The columns of information change based on the type of information (USE, CLAIMERS, LOCKS, LPL, WEPR) requested.

All options have these columns in common: NAME, TYPE, PART STATUS.

USE: NAME, TYPE, PART  STATUS, CONNID, CORRID, USERID
CLAIMERS: NAME, TYPE, PART  STATUS, CONNID, CORRID, CLAIMINFO
LOCKS: NAME, TYPE, PART  STATUS, CONNID, CORRID, LOCKINFO
LPL: NAME, TYPE, PART  STATUS, LPL PAGES
WEPR: NAME, TYPE, PART  STATUS, PHYERRLO, PHYERRHI, CATALOG, PIECE

If an information parameter type isn't specified, the default columns are based on WEPR format. Here's the basic command that I’ve used for years to find any objects in a restricted state:

-DIS DB(*) SPACE(*) RESTRICT

As another example, say you've made some changes to an object and DB2 is advising a reorg. To find these notifications, issue this command:

-DIS DB(*) SPACE(*) RESTRICT ADV(AREO*)

IBM has improved DISPLAY DATABASE over the past few releases by providing some nice filtering capabilities. First, you can filter on the object name through wild cards:

-DIS DB(dbname*)          : Display all database names starting with dbname
-DIS DB(*dbname)        : Display all database names ending with dbname.
-DIS DB(*dbname*)        : Display database names that contain dbname
-DIS DB(dbname1:dbname2)    : Display all database names between dbname1 and dbname2
-DIS DB(*dbstring1*dbstring2)    : Display all database names that contain string1 and string2

This same type of filter works with the space name parameter.

When DISPLAY DATABASE is issued, it displays only 50 lines (the default setting). To increase this setting, use the LIMIT keyword. LIMIT(100), for example, would display 100 lines of output. To see all output without limit, use LIMIT(*).

A final tip: When issuing a command with a parameter such as LOCKS, you'll get all rows for the name filter, even if the object doesn't have a lock associated with it. So use the very handy ONLY parameter to return only the rows that contain locks. For example, here's how you'd display all objects on the system that have active locks:

-DIS DB(*) SPACE(*) LOCKS LIMIT(*) ONLY

So what have you learned from your own use of the display database command? Please share your experiences in Comments.