kuddb2 process randomly crashes
An instance of ITM DB2 agent V6.2.2, used to monitor a DB2 V9.1 Workgroup Server Edition, crashes from time to time.The problem does not occur when using the same ITM agent level to monitor a DB2 V9.1 Enterprise Edition.
The errpt shows the following information about process crash :
SIGNAL NUMBER : 11
USER'S PROCESS ID: 07968
FILE SYSTEM SERIAL NUMBER : 10
INODE NUMBER : 28773
CORE FILE NAME : /opt/itm/logs/exec/ud/core
PROGRAM NAME : kuddb2
STACK EXECUTION DISABLED
COME FROM ADDRESS REGISTER
Diagnosing the problem
Further analysis of the DB2 log (db2diag) highlights that kuddb2 process crashes when it tries
to perform an sqlconnect function and the target database is in quiesce status.
The quiesce is issued in example before starting an offline DB backup.
Resolving the problem
This is not an ITM DB2 agent failure.It is a DB2 defect, and occurs only under specific circumstances.
If, into db2cli.ini file, you have set CurrentSchema, this triggers a communication round trip to the server side .
If during this communication the quiesce database with the force connections option is issued, as in the case of kuddb2 process, then that causes an error in the communication layer.
This nulls out the "half established" connection and this null connection is accessed once more prior to the return code check.. leading to the crash.
This is a problem occurring in DB2 v9.1 and DB2 v9.5 but it does not occur with DB2 9.7.
An APAR has been opened for DB2 9.5 : IC87545.
No fix will be delivered for 9.1 as it is out of support.
From ITM DB2 agent perspective, you can also use the following workaround :
The environment variable DB2CLIINIPATH can be used to override
the default and specify a different location for the db2cli.ini file.
1) Create a new .ini file,in example call it db2cli_kuddb2.ini and copy the content from the original one.
2) Remove the database specific entries and save the file.
3) Set the following environment variable before starting the DB2 monitoring agent :
This should help circumventing the problem.
IBM Tivoli Monitoring DB2 Agent V6.2.2
More support for:
Tivoli Composite Application Manager for Applications
ITCAM Agent for DB2 - 5724B96DO
Software version: 6.2.2
Operating system(s): AIX
Reference #: 1617714
Modified date: 19 November 2012