DB2 - Problem description
Problem IC83352 | Status: Closed |
BAD PAGE HEADER ENCOUNTERED BY PREFETCHER DURING ONLINE BACKUP ON LINUX PLATFORM. BACKUP IMAGE MAY BE CORRUPTED. | |
product: | |
DB2 FOR LUW / DB2FORLUW / 980 - DB2 | |
Problem description: | |
This problem exists on the Linux platform only. Conditions through which the Bad Page Header is encountered: 1) Linux operating system 2) DB2 V9.8 3) Tablespaces with multiple containers 4) Online backup 5) Significant user activity which drives prefetching during online backup There are 2 possible consequences: 1) Incorrect pages are silently written to the online backup. Any restore from this backup image will result in data corruption. 2) Bad Page Header messages encountered by prefetchers during the online backup. 2011-06-01-21.04.29.871752-240 I495774E3614 LEVEL: Severe PID : 11263 TID : 47129540159808PROC : db2sysc INSTANCE: db2inst1 NODE : 000 EDUID : 134 EDUNAME: db2pfchr (SAMPLE) FUNCTION: DB2 UDB, buffer pool services, sqlb_verify_page, probe:13 MESSAGE : ZRC=0x87020036=-2029912010=SQLB_BADHDR "Bad Page Header" DIA8547C An error occurred in a database page header. DATA #1 : String, 64 bytes Error encountered trying to read a page - information follows : DATA #2 : String, 23 bytes Page verification error DATA #3 : Page ID, PD_TYPE_SQLB_PAGE_ID, 4 bytes 9678 DATA #4 : Object descriptor, PD_TYPE_SQLB_OBJECT_DESC, 88 bytes Obj: {pool:4;obj:4;type:1} Parent={4;4} lifeLSN: 0000000010F75884 tid: 0 0 0 extentAnchor: 8490 initEmpPages: 0 poolPage0: 0 poolflags: 3122 objectState: 27 lastSMP: 0 pageSize: 16384 extentSize: 2 bufferPoolID: 2 partialHash: 17039364 bufferPool: 0x00002adc27f347c0 pdef: 0x00002adc2de8aec0 DATA #5 : Bitmask, 4 bytes 0x00000002 DATA #6 : Page header, PD_TYPE_SQLB_PAGE_HEAD, 48 bytes pageHead: {tbspSeed:4;obj:4;type:0} PPNum:2770 OPNum:2762 begoff: 48 datlen: 16336 pagebinx: 0 revnum: 1280 pagelsn: 000000000238ED4C flag: 2 future32: 0 cbits1to31: 1c02807 cbits32to63: 0 CALLSTCK: [0] 0x00002ADBBF2955A2 pdLog + 0x398 [1] 0x00002ADBBFF73186 _Z25sqlbLogReadAttemptFailurejP16SQLB_OBJECT_DESCjP9SQLB_PAGEibm jPcP12SQLB_GLOBALS + 0x1BE [2] 0x00002ADBC1A59352 _Z16sqlb_verify_pageP9SQLB_PAGEP16SQLB_OBJECT_DESCjjP12SQLB_GLOB ALSPm + 0x376 [3] 0x00002ADBBF2CDFF8 _Z25sqlbReadAndReleaseBuffersP16SQLB_OBJECT_DESCjmmmP11SQLB_pfMi sc + 0x984 [4] 0x00002ADBBF2CC538 _Z16sqlbProcessRangeP16SQLB_OBJECT_DESCjjP11SQLB_pfMisc + 0x140 [5] 0x00002ADBBF2CB7B7 _Z26sqlbPFPrefetcherEntryPointP16sqbPrefetcherEdu + 0x3C9 [6] 0x00002ADBBF2CB3AD _ZN16sqbPrefetcherEdu6RunEDUEv + 0x2F [7] 0x00002ADBBFA9732C _ZN9sqzEDUObj9EDUDriverEv + 0xA6 [8] 0x00002ADBBFA97283 _Z10sqlzRunEDUPcj + 0x9 [9] 0x00002ADBBF80B3D2 sqloEDUEntry + 0x2F4 The db2diag.log entries in the above example show that DB2 requested page 9678 from tablespace 4, but received page 2770 from tablespace 4. In order to verify the occurrence of the bad page header issue, the received page must be in the same tablespace as the requested page. | |
Problem Summary: | |
**************************************************************** * USERS AFFECTED: * * DB2 V9.8 pureScale on Linux * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to V98 Fixpack 5 * **************************************************************** | |
Local Fix: | |
For the following command: db2set DB2BPVARS=<file> Replace <file> with a fully qualified file name, such as /home/db2inst1/bpvars.cfg Place the following line in the stated file: NOREADVBCKUP=1 Restart DB2 to propagate changes. | |
Solution | |
See Error Description | |
Workaround | |
not known / see Local fix | |
Timestamps | |
Date - problem reported : Date - problem closed : Date - last modified : | 11.05.2012 21.06.2012 01.07.2012 |
Problem solved at the following versions (IBM BugInfos) | |
9.8.FP5 | |
Problem solved according to the fixlist(s) of the following version(s) | |
9.8.0.5 |