Relink Action Holddata In Top Secret For DB2 Fix LU16054

Products

• Top Secret

Issue/Introduction

One of the HOLDDATA actions for Top Secret for DB2 fix LU16054 is to perform the following step:

3. Run CADBJCL0(DB13XAC) to Relink DSNX@XAC for Top Secret.

There is some hesitation about relinking this exit as it has not been done in a long time. Can you explain why this is needed and if not done, what would be the ramifications of implementing the maintenance without doing the relink?

Resolution

DB2 exit CADB2XAC is a replacement for a DB2 provided exit that was added to provide RACF with the ability to provide DB2 resource authorization. At the time of its introduction, Top Secret already had a different method to provide ESM security to DB2. Because of this, the exit was provided to ensure that the correct DB2 security controls were in place. 

DB2 utility products that run outside of the DB2 engine needed a way to check ESM access to DB2 resources, so the exit was modified to be callable in a non-DB2 environment, which was delivered in PTF RO88020. An enhancement was made to this support, via PTF LU09780, for processing in a data sharing environment. However, it was reported this change lead to a performance degradation, primarily in a JES3/JES3+ environment. LU16054 was written to address and alleviate this degradation.

If the exit wasn't relinked to address LU09780, it won't be required to perform the relink for LU16504. Also, if you are not running BMC DB2 Utilities, such as LOAD PLUS or REORG PLUS (among others), this exit does not need to be relinked.