IBM Support

ISCDC: Critical data loss with specific CDC patches

Flash (Alert)


We have uncovered a critical data loss issue with the following CDC patches.
1) 6.5.1 interim fix 1 for Oracle
2) 6.5.1 interim fix 1 for Oracle (Trigger)
3) 6.5.0 interim fixes 31 and 32 for Oracle
4) 6.5.0 interim fixes 12 and 13 for DB2 LUW
Please see APAR JR40911



The data loss is unpredictable and occurs at the communications layer when the comms queue becomes full. This behavior will not be obvious to the user.

Possible Consequence/Impact:
Data Loss

There is a field work-around. Set the SOURCE system parameter global_statistics_blocking_threshold_milliseconds to a very high value, such as 6854775808,
followed by a restart of the CDC instance

Fix Availability
The permanent fix for this issue is expected to be available on Oct. 31, 2011

Document information

More support for: InfoSphere Change Data Capture

Software version: 6.5, 6.5.1

Operating system(s): AIX, HP-UX, Linux, Solaris

Reference #: 1568498

Modified date: 25 October 2011