A fix is available
APAR status
Closed as program error.
Error description
CICS emergency restart fails with: DFHNQ0002 A severe error (code X'0212') has occurred in module DFHNQNQ DFHRM0002 A severe error (code X'069A') has occurred in module DFHRMR1D. . Two tasks are writing to an extended, recoverable ESDS file. Task1 has completed it's file WRITE and a corresponding WRITE_ADD and WRITE_ADD_COMPLETE have both been logged. Task2 has logged it's WRITE_ADD to the same file but CICS abended before the record was written to VSAM, and so before the WRITE_ADD_COMPLETE was logged. . On the subsequent emergency restart, DFHFCIR correctly reacquires the FCDSESWR write lock for task2 because there was no WRITE_ADD_COMPLETE record on the system log. DFHFCIR then encounters the WRITE_ADD_COMPLETE record for task1, but does not set flag FLAB_WA_COMPLETE_SEEN. So when DFHFCIR encounters the WRITE_ADD record, it doesn't remember it, and assumes a WRITE request must have been incomplete and attempts to acquire the FCDSESWR write lock. This causes a locked error and message DFHNQ0002 0212 is issued. Trace shows: . NQ 0212 NQNQ *EXC* - Enqueue_locked_error - FUNCTION(REACQUIRE_ENQUEUE) . This problem occurs because DFHFCIR incorrectly ignores the WRITE_ADD_COMPLETE record for an extended ESDS file. . Additional Symptom(s) Search Keyword(s): KIXREVEAA 212 0212 FCDSRECD NQ0002 RM0002
Local fix
Problem summary
**************************************************************** * USERS AFFECTED: All CICS Users. * **************************************************************** * PROBLEM DESCRIPTION: A CICS system experienced an outage, * * and was restarted using EMERGENCY * * restart. During this restart CICS * * encountered message DFHNQ0002 A severe * * error (code X'0212') has occurred in * * module DFHNQNQ. * **************************************************************** * RECOMMENDATION: * **************************************************************** A CICS system experienced an outage. At the time of the outage there had been two inflight tasks both writing to the same Extended Addressing ESDS file. CICS was then restarted using EMERGENCY restart. During this restart CICS read the File Control journal entries in DFHLOG, and tried to back out these two tasks. CICS then encountered message DFHNQ0002 A severe error has occurred (code X'0212') in module DFHNQNQ, followed by DFHRM0002 A severe error has occurred (code X'069A') in module DFHRMR1D. Trace point NQ 0212 *EXC* Enqueue_locked_error was also issued, and CICS shut down. . When writing to an Extended Addressing ESDS CICS first writes an 83 (write-add) record to DFHLOG, then calls VSAM to perform the write. It is only at this point that the location the record is written to is confirmed. When VSAM completes the write it returns to CICS the RBA used, and CICS writes an 84 (write-add-complete) record to DFHLOG which should contain this RBA. These records are then used to perform backout. . The problem here was twofold; the primary problem was that the 84 records were not being processed by CICS during the emergency restart. This led to a situation where both tasks attempted to get the ESDS file write lock (FCDSESWR), leading to a conflict and giving rise to the NQ0002 error. In addition the RBA information (stored in field fljb_cd_key) was missing from the 84 record. Additional keywords: msgDFHNQ0002 msgDFHRM0002
Problem conclusion
DFHFCIR has been altered so that the 84 log records are read in and processed correctly. DFHFCLJ has also been altered so that the actual RBA used by VSAM to perform the write, for an extended ESDS, is written out to the 84 record in field fljb_cd_key. Field fljb_cd_key_length in the record has also be corrected such that it now contains the length of the key. These two changes together allow backout to proceed correctly, since the 84 log record now contains the required information, and is being processed.
Temporary fix
********* * HIPER * ********* FIX AVAILABLE BY PTF ONLY
Comments
APAR Information
APAR number
PM16633
Reported component name
CICS TS Z/OS V4
Reported component ID
5655S9700
Reported release
600
Status
CLOSED PER
PE
NoPE
HIPER
YesHIPER
Special Attention
NoSpecatt
Submitted date
2010-06-17
Closed date
2010-07-28
Last modified date
2010-09-02
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
UK59267
Modules/Macros
DESFCIR DESFCLJ DFHFCIR DFHFCLJ DFHFCLJA DFHFCLJM DFHFCLJT
Fix information
Fixed component name
CICS TS Z/OS V4
Fixed component ID
5655S9700
Applicable component levels
R600 PSY UK59267
UP10/08/05 P F008
Fix is available
Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.
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Document Information
Modified date:
02 September 2010