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CICS abend but no system dump is generated

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Abstract

You are not getting a system dump for an abend in your CICS Transaction Server for z/OS (CICS TS) region. You need a dump at the time of the error so that you can determine why the abend is occurring. You have the choice of two different types of CICS dumps to help you with problem determination. They are the transaction dump, that only contains storage related to the transaction that abended. And the CICS system dump, that contains storage from the entire CICS region. The type of dump to use for problem determination depends on the nature of the problem. In practice, the system dump is often more useful, because it contains more information than the transaction dump. The focus of this document is on how to stop CICS from suppressing a system dump.

Body

A dump can be suppressed in various ways. You can use DAE and DUMP parameters to suppress the dump globally:

  • DAE (Dump Analysis and Elimination) is a z/OS parameter that allows an installation to suppress SVC dumps and SYSMDUMP ABEND dumps. DAE only suppresses dumps that it believes are duplicates, or similar to one that occurred recently within a given period of time. If DAE is suppressing dumps, you need to reset DAE so that it will allow a dump to be taken if the problem happens again. Or, you can just set the DAE parameter to No so the system dump will no longer be suppressed by the MVS Dump Analysis and Elimination component.
  • DUMP is a CICS system initialization table (SIT) parameter that is allows you to suppress or enable system dumps. Besides coding a value of YES for the DUMP parameter in the SIT, you can also use the CEMT command to change the dump option on-the-fly to allow CICS to start taking dumps without recycling the region. To change the DUMP attribute, you can enter one of the following commands:

If system dumps are not suppressed by either of the above mechanisms, the dump table options determine whether or not you get a dump for a particular dump code. You can inquire on transaction and system dump code attributes using CEMT INQ TRDumpcode and CEMT INQ SYDumpcode respectively. From the command output, place the cursor on the result that you are interested in and press "ENTER".  CICS will display an expanded format for the dump code that is a little easier to read and overtype.  Look first to see if attribute SYSDUMP is specified for the dump code. The attribute needs to be SYSDUMP if a system dump is to be taken. If the attribute is shown to be SYSDUMP, look next at the maximum number of dumps specified for the dump code, and compare it with the current number. If they are the same, it means the maximum number of dumps have already been taken, and you need to reset the current value to zero.

Below are two common commands to cause system dumps to be taken:

  • CEMT SET TRDUMPCODE(trdumpcode) SYSDUMP MAX(1) ADD
  • CEMT SET SYDUMPCODE(sydumpcode) SYSDUMP MAX(1) ADD

For example, if you want the region to take a system dump on abend code AD2R, you can enter:

CEMT SET TRD(AD2R) SY MAX(1) ADD

If you want a dump to be taken on CICS message DFHAP0001, you can enter:

CEMT SET SYD(AP0001) SY MAX(1) ADD

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ibm11080777

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