- Application of captured changes by downstream Engine has been or must be interrupted for a short time due to system outage, communication failure, Engine failure, Engine script modification, etc.
Solution: Temporarily stop Publisher Agent. See the next section Stopping the CDCzLog Publisher Agent for instructions.
- Application of captured changes by downstream Engine or must be interrupted for an extended time due to system outage, communication failure, Engine failure, Engine script modification, etc.Solution: Disable capture by regenerating the XPARM control module, specifying DISABLE=Y using JCL similar to GENXPRIS included in the distribution and then apply the changes using SQDAUPDX which, dynamically updates the XPARM control module in real-time.Note: This stops changes from being written to the LogStream meaning those changes are lost from capture.
- Data Capture no longer required for specific Source Data segment.
Solution: The solution depends, in part, how capture was specified in the DBD. If the Exit parameter is specified at the segment level then the DBD should be updated to remove that Exit specification. If capture was specified with the Exit parameter at the DBD level, either the DBD can be revised to segment level specification or the XPARM control module can be updated to specify a destination target of DUMMY for the segment to be excluded from capture. level in the DBD. Often the quickest way to disable Capture of a particular IMS segment(s) without modifying the DBD is to exclude the segment by updating the XPARM control module.
- Data Capture no longer required for ANY Source Data.
Solution 1: Removing the EXIT keyword(s) from the DBD keeps IMS from calling the IMS Data Capture Agent for the database/segment(s) in which the EXIT keyword was previously specified. If you have other data capture exits defined for a particular IMS database/segment or you are sending changed data to the recovery logs (using the EXIT=*,LOG keyword), you can simply remove the reference to the IMS Data Capture Agent from the EXIT statement.
Solution 2: Replace the IMS Data Capture Agent module (SQDICDCL) with the SQDATA ‘dummy’ module (SQDABR14) shipped with Connect CDC SQData. This is done using the JCL member SQDLBR14 supplied in the SQDATA.CNTL library. You must first modify the name of the link-edited module to SQDICDCL in the SQDLBR14 JCL.Note: This stops changes from being written to the LogStream meaning those changes are lost from capture.
There are multiple methods for permanently or temporarily disabling data capture. Selecting which method to use depends on the reason for doing so. The following scenarios suggest the method to use based on the reason: