Potential loss of data for DB2 v10 users on z/OS 1.12 and 1.13 releases
DB2 V10 and PDSE users potentially affected by error in z/OS Media Manager IO recovery. Users of zDMF running zHPF may be particularly exposed because all I/O requests are intercepted by zDMF and returned to Media Manager in error for IO redrive using FICON, however any I/O errors, including interface control check and unit checks, that are retried by the media manager are also subject to the problem.
There are certain situations where the Media Manager will redrive the failed channel program with a different type of channel program. In some highly timing dependant cases, such as with I/Os that cross extents, the redrive may not occur correctly, and no error is presented to the caller, potentially leading to data being down level on disk. The problem may occur for DB2 V10 or PDSE data sets. Please see APAR OA42277 for more details.
Also please do not use zDMF until the fix for OA42277 is applied.
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