Troubleshooting

 

When a problem occurs accessing a distributed relational database, it is the job of the administrator to determine the nature of the problem and whether it is a problem with the application or a problem with the local or remote system.

You must then resolve the problem or obtain customer support assistance to resolve the problem. To do this, you need:

• An understanding of the i5/OS^® licensed program support.

• A good idea of how to decide if a problem is on an application requester (AR) or an application server (AS).

• Familiarity with using i5/OS problem management functions.

For more information about diagnosing problems in a distributed relational database, see the Distributed Relational Database Problem Determination Guide, SC26-4782.

• i5/OS problem handling overview
  The i5/OS licensed program helps you manage problems for both user-detected and system-detected problems that occur on local and remote System i™ platforms.

• Isolating distributed relational database problems
  A problem you encounter when running a distributed relational database application can exhibit two general symptoms: incorrect output or the application does not complete in the expected time.

• Working with distributed relational database users
  Investigating a problem usually begins with the user. Users might not be getting the results they expect when running a program or they might get a message indicating a problem. Sometimes the best way to diagnose and solve a problem is to go through the procedure with a user.

• Application problems
  The best time to handle a problem with an application is before it goes into production. However, it is impossible to anticipate all the conditions that will exist for an application when it gets into general use.

• System and communications problems
  When a problem with a system or its communications occurs, a message is generated. System-detected problems are automatically entered into the problem log, where they can be viewed and analyzed.

• Getting data to report a failure
  The i5/OS licensed program provides data that you can print to help you diagnose a problem in a distributed relational database.

• Finding first-failure data capture data
  You can use the tips in this topic to locate first-failure data capture (FFDC) data on the i5/OS operating system. The information is most useful if the failure causing the FFDC data output occurred on the application server (AS). The FFDC data for an application requester (AR) can usually be found in one of the spooled files associated with the job running the application program.

• Starting a service job to diagnose application server problems
  When an application uses Distributed Relational Database Architecture™ (DRDA^®), the SQL statements are run in the application server job. Because of this, you might need to start debug or a job trace for the application server job that is running on the i5/OS operating system. The technique for doing this differs based on the use of either Advanced Program-to-Program Communication (APPC) or TCP/IP.

 

Parent topic:

Distributed database programming

 

Related concepts

Performance