Tracing the IFI API

Use the new TRACE configuration to trace the DB2 IFI API being used by Replication Agent for DB2 UDB to read DB2 log records.

Syntax

TRACE=IFI

When this trace is turned on, Replication Agent for DB2 UDB displays trace messages with information about the IFI process.

Because this trace produces a large amount of output, use it only temporarily to research a problem that appears to be related to the DB2 database. Sybase Technical Support personnel may request that you start Replication Agent for DB2 UDB with this trace turned on when they are researching a problem.

LTMIFI output

This example shows typical Log Transfer Manager Instrumentation Facility Interface (LTMIFI) output when the IFI trace is on:

Example 3

LTMIFI initialization              
LTMIFI WLI RC=00000004 RES=00E60800
LTMIFI IFI read H
LTMIFI IFI read F  
LTMIFI Check 306           
LTMIFI records read   116

IFI return codes

When the IFI trace is on, all return codes from the DB2 IFI API are displayed with a short explanation, even though you can ignore the messages. For example:

Example 4

IFI 04/00E60804 No data was returned for the request

The return code 04 indicates that the message is a warning. Messages with return codes higher than 04 are always traced and placed on the console.

Messages that are returned when the IFI trace is on are not preceded by “LTM.” This helps these messages stand out from all the other LTM console messages, because they may require immediate attention or may be the cause for an abnormal termination.

Example

In this example, a bootstrap data set (BSDS) is made unavailable at start-up and an invalid Relative Byte Address (RBA) is used to start Replication Agent for DB2 UDB. These issues may cause the IFI interface to become unstable and Replication Agent for DB2 UDB to terminate abnormally.

The IFI message makes this information available to the operator immediately so that he or she can make changes before restarting Replication Agent for DB2 UDB is with a valid RBA field.

Example 5

LEX0025 Log processing to begin at log RBA 0000000000FF.                        
IFI 08/00E60863 A resource was unavailable for a READS 306 
LEXTRACE Read Error rc=00000008 reason=00E60863

See the IBM DB2 version 9.1 for z/OS documentation for more examples of the TRACE command.