Monitor db integrity / block corruption

Hi
Im trying to proactively monitor for block corruptions / integrity problems in oracle environments….
Will it suffice if I query below views and send output to dbas on regular basis?
select * from V$DATABASE_BLOCK_CORRUPTION;
select * from v$backup_corruption;
v11.2.0.3.0
Edited by: user9182826 on Jan 14, 2013 1:53 PM

JohnWatson wrote:
user9182826 wrote:
JohnWatson wrote:
Those views will tell about blocks that have been found to be corrupt during an RMAN backup operation. OK, but RMAN doesn't necessarily look at every block. You might want to be a bit more proactive: run dbv against the datafiles.so those views will always remain empty if im not using rman to backup my db ?If you do not believe me, you can always check the documentation.
(by the way, you might want to say "thank you": it would encourage more replies)thousands thank you! , you made my day lol

Similar Messages

Logical Block corruption - not enough RMAN backups

I have to deal with logical block corruption but these guys do not have enough rman backups to go back enough to recover blocks.
All bad blocks are in SYSAUX and it seems because of it EM doesn't work as it's suppose to do. I dropped and recreated EM repository hoping it will clean itself but .... no.
Any ideas?
Oracle Linux 4.7 i386
Oracle 10.2.0.4

OCCUPANT_NAME OCCUPANT_DESC SCHEMA_NAME MOVE_PROCEDURE MOVE_PROCEDURE_DESC SPACE_USAGE_KBYTES
EM Enterprise Manager Repository SYSMAN emd_maintenance.move_em_tblspc Move Procedure for Enterprise Manager Repository 52800
EM_MONITORING_USER Enterprise Manager Monitoring User DBSNMP *** MOVE PROCEDURE NOT APPLICABLE *** 1600

Block corruption

Hi,
I used DBV utility to check block corruption in each datafile and it returned no corrupt block. So for redolog files i used the same utility and it given a long list of info which i can't rectify what that means? there is block corruption in redolog files or this something else.
DBVERIFY - Verification starting : FILE = /oracle/BP3/origlogA-New/log_g1m1.log
Page 1 is influx - most likely media corrupt
Corrupt block relative dba: 0x00000001 (file 0, block 1)
Fractured block found during dbv:
Data in bad block:
type: 1 format: 2 rdba: 0x00000001
last change scn: 0x8000.0002b7af seq: 0x5e flg: 0xbd
spare1: 0x0 spare2: 0x0 spare3: 0x0
consistency value in tail: 0x00000000
check value in block header: 0x0
computed block checksum: 0x0
Page 2 is marked corrupt
Corrupt block relative dba: 0x00000002 (file 0, block 2)
Bad header found during dbv:
Data in bad block:
type: 1 format: 2 rdba: 0x00000002
last change scn: 0x8010.0002b7af seq: 0x98 flg: 0x7e
spare1: 0x0 spare2: 0x0 spare3: 0x70
consistency value in tail: 0x00030003
check value in block header: 0x0
computed block checksum: 0x0
Page 3 is marked corrupt
Corrupt block relative dba: 0x00000003 (file 0, block 3)
Bad header found during dbv:
Data in bad block:
type: 1 format: 2 rdba: 0x00000003
last change scn: 0x8010.0002b7af seq: 0x4d flg: 0x21
spare1: 0x0 spare2: 0x0 spare3: 0x3f8
consistency value in tail: 0x41ffffff
check value in block header: 0x0
block checksum disabled
and goes on
Thanks and Regards
Jafar

Hi,
DB Verify
DB_VERIFY (dbv) is a utility than can be used to perform a physical structure integrity check against off-line database files.
This utility runs perfectly well against on-line files as well, however, the manual is clear that it is an off-line utility. My assumption is that it may incorrectly report blocks as bad while I/O is taken place (fractured blocks).
DBA 's should use this utility frequently to identify datafiles that are corrupted. Some times the database will perform normally until you address a particular block in the datafile, which may then result in ORA-600 errors.
DB_VERIFY is useful in these situations:
When block corruption is expected;
Forecast any future problems w.r.t. database file/ block corruption;
When you restore files from a tape. It will help knowing if the first file pulled from tape is corrupt, instead of spending hours to extract all of them.
To access help on DB_VERIFY type:
DSS-BWDB:orabp3 2% dbv help=y
DBVERIFY: Release 10.2.0.2.0 - Production on Fri Feb 8 15:52:02 2008
Copyright (c) 1982, 2005, Oracle. All rights reserved.
Keyword Description (Default)
FILE File to Verify (NONE)
START Start Block (First Block of File)
END End Block (Last Block of File)
BLOCKSIZE Logical Block Size (8192)
LOGFILE Output Log (NONE)
FEEDBACK Display Progress (0)
PARFILE Parameter File (NONE)
USERID Username/Password (NONE)
SEGMENT_ID Segment ID (tsn.relfile.block) (NONE)
HIGH_SCN Highest Block SCN To Verify (NONE)
(scn_wrap.scn_base OR scn)
EXAMPLE
$ dbv file=/u01/oradata/o10gr2/example01.dbf
DBVERIFY: Release 10.2.0.1.0 - Production on Sat Jul 7 11:45:52 2007
Copyright (c) 1982, 2005, Oracle. All rights reserved.
DBVERIFY - Verification starting : FILE = /u01/oradata/o10gr2/example01.dbf
DBVERIFY - Verification complete
Total Pages Examined : 12800
Total Pages Processed (Data) : 4409
Total Pages Failing (Data) : 0
Total Pages Processed (Index): 1264
Total Pages Failing (Index): 0
Total Pages Processed (Other): 1539
Total Pages Processed (Seg) : 0
Total Pages Failing (Seg) : 0
Total Pages Empty : 5588
Total Pages Marked Corrupt : 0
Total Pages Influx : 0
Highest block SCN : 470536 (0.470536)
You can use dbv utility for datafiles not for tempfiles, redolog file, controlfile etc.
download-west.oracle.com/docs/cd/B10501_01/server.920/a96652/ch13.htm
Regards
Jafar

ORA-01578: ORACLE data block corrupted on tables in sysaux tablespace

Dear Experts,
From the alert log file we noticed data block corruptions on one of our datafiles. After further investigation, we realized that the corruptions were on 3 of the AWR related tables in the SYSAUX tablespace:
1. WRH$_LIBRARYCACHE
2. WRH$_TEMPSTATXS
3. WRI$_ALERT_OUTSTANDING
The bad news is that we may not have a valid rman backup to do the recovery due to the retention policy - RECOVERY WINDOW OF 2 DAYS. Since this is a development database with limited monitoring, we did not discover the corruption until 6 days later. The issue happened about 6 days ago (about Christmas time).
So, what are our recovery options? Can someone advice? We are thinking about drop and recreate the 3 affected v$WR* tables, but not quite sure about the impact to the system if we drop and recreate the 3 objects. Did someone experience this type of recovery. If you did, what are your approaches?
We are running oracle 10.2.0.3 version.
I greatly appreciate your input and suggestion. Thanks!!!

as long as you have a backup of ur database before christmas, you can use the " MAXDAYS " cmd to get ur backup working so long as you have not used delete obsolote....had a same sistuation....where i had a backup and trying to restore it ...kept saying no valid backup...after going thru some stuff...found the MAXDAYS cmd to use my backup...here is an example ...
$ rman target /
Recovery Manager: Release 10.2.0.2.0 - Production on Sun Apr 6 09:05:44 2008
Copyright (c) 1982, 2005, Oracle. All rights reserved.
connected to target database (not started)
RMAN> SET DBID=1528894801
executing command: SET DBID
RMAN> startup force nomount;
startup failed: ORA-01078: failure in processing system parameters
LRM-00109: could not open parameter file '/u01/app/oracle/product/10.2.0/db_1/dbs/initsameera.ora'
starting Oracle instance without parameter file for retrival of spfile
Oracle instance started
Total System Global Area 159383552 bytes
Fixed Size 1259672 bytes
Variable Size 58722152 bytes
Database Buffers 92274688 bytes
Redo Buffers 7127040 bytes
RMAN> set controlfile autobackup format for device type disk to '/u99/backup/sameera/control_spfile_%F';
executing command: SET CONTROLFILE AUTOBACKUP FORMAT
using target database control file instead of recovery catalog
RMAN> run
2> {
3> allocate channel p1 type disk;
4> restore spfile to pfile '/u01/app/oracle/product/10.2.0/db_1/dbs/initsameera.ora' from autobackup;
5> shutdown abort;
6> }
allocated channel: p1
channel p1: sid=36 devtype=DISK
Starting restore at 06-APR-08
channel p1: looking for autobackup on day: 20080406
channel p1: looking for autobackup on day: 20080405
channel p1: looking for autobackup on day: 20080404
channel p1: looking for autobackup on day: 20080403
channel p1: looking for autobackup on day: 20080402
channel p1: looking for autobackup on day: 20080401
channel p1: looking for autobackup on day: 20080331
channel p1: no autobackup in 7 days found
released channel: p1
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of restore command at 04/06/2008 09:09:09
RMAN-06172: no autobackup found or specified handle is not a valid copy or piece
Solution:
RMAN> shutdown abort;
RMAN> EXIT;
$ ps -ef |grep pmon
oracle 2891 2856 0 09:05 pts/1 00:00:00 grep pmon
oracle 7448 1 0 Apr05 ? 00:00:00 ora_pmon_primary
$export ORACLE_SID=sameera
$ rman target /
Recovery Manager: Release 10.2.0.2.0 - Production on Sun Apr 6 09:05:44 2008
Copyright (c) 1982, 2005, Oracle. All rights reserved.
connected to target database (not started)
RMAN> SET DBID=1528894801
executing command: SET DBID
RMAN> startup force nomount;
startup failed: ORA-01078: failure in processing system parameters
LRM-00109: could not open parameter file '/u01/app/oracle/product/10.2.0/db_1/db s/initsameera.ora'
starting Oracle instance without parameter file for retrival of spfile
Oracle instance started
Total System Global Area 159383552 bytes
Fixed Size 1259672 bytes
Variable Size 58722152 bytes
Database Buffers 92274688 bytes
Redo Buffers 7127040 bytes
RMAN> set controlfile autobackup format for device type disk to '/u99/backup/sameera/control_spfile_%F';
executing command: SET CONTROLFILE AUTOBACKUP FORMAT
using target database control file instead of recovery catalog
RMAN> run
2> {
3> allocate channel p1 type disk;
4> restore spfile to pfile '/u01/app/oracle/product/10.2.0/db_1/dbs/initsameera.ora' from autobackup maxdays 15;
5> shutdown abort;
6> }
released channel: ORA_DISK_1
allocated channel: p1
channel p1: sid=36 devtype=DISK
Starting restore at 06-APR-08
channel p1: looking for autobackup on day: 20080406
channel p1: looking for autobackup on day: 20080405
channel p1: looking for autobackup on day: 20080404
channel p1: looking for autobackup on day: 20080403
channel p1: looking for autobackup on day: 20080402
channel p1: looking for autobackup on day: 20080401
channel p1: looking for autobackup on day: 20080331
channel p1: looking for autobackup on day: 20080330
channel p1: looking for autobackup on day: 20080329
channel p1: looking for autobackup on day: 20080328
channel p1: looking for autobackup on day: 20080327
channel p1: looking for autobackup on day: 20080326
channel p1: looking for autobackup on day: 20080325
channel p1: looking for autobackup on day: 20080324
channel p1: looking for autobackup on day: 20080323
channel p1: autobackup found: /u99/backup/sameera/control_spfile_c-1528894801-20080323-00
channel p1: SPFILE restore from autobackup complete
Finished restore at 06-APR-08
Oracle instance shut down
Check to make sure if initsameera.ora exists in $ORACLE_HOME/dbs location.
$ cd $ORACLE_HOME/dbs
$ ls -ltr
total 7052
-rw-r----- 1 oracle oinstall 2560 Apr 5 13:21 spfileprimary.ora
-rw-r----- 1 oracle oinstall 7061504 Apr 5 13:23 snapcf_primary.f
-rw-rw---- 1 oracle oinstall 1544 Apr 5 18:42 hc_sameera.dat
-rw-r--r-- 1 oracle oinstall 1087 Apr 6 09:12 initsameera.ora
$ pwd
/u01/app/oracle/product/10.2.0/db_1/dbs
$

Windows and RAC block corruption

Hi,
we're using rac / windows / 9204 with a san and ocfs and we're getting loads of block corruptions (ora-1578).
We're using dbms_repair to isolate the problems and read 'past' the data, but this is obviously not ideal since we loose data.
Besides proprietary SAN disk checking programs, dbms_repair,analyze and dbverify - are there any other mechanisms one could use to check disk integrity?
Regards
Ottar.

user496020 wrote:
Hi,
The other day I was importing a csv file. Not long thereafter that I got an error message:
ORA-01578: ORACLE data block corrupted (file # 28, block # 757)
ORA-01110: data file 28: '/u02/oradata/APEX/APX_APPL01_02.dbf'Your database is corrupt, you need to perform some recovery on the affected data files, etc.

I need to monitor a transducer block parameter and save it to a CSV file.

How can I monitor a transducer block parameter and save it to a CSV file? The reason is that I need to do some long-term testing of an FFb device we are developing, and I need to read the primary output parameter of the transducer block (not the scheduled AI block) every second or two and save to a CSV file.
I have tried to figure out a way to do that with FBUS Configurator, unsuccessfully, and I purchased FBUS Monitor, as that was recommended by an industry expert, but I have been unsuccessful at getting that to work as well.

Hi Wpinson,
Neither FBUS Configurator nor Monitor can meet your requirement. However, there are other approaches. NI-FBUS provides APIs for C, LabVIEW, VB and C#. You can use these APIs to read a parameter value of any block and use standard file IO functions to save the date into CSV file. The LabVIEW APIs are highly recommended because they are easy-to-use and LabVIEW also provides APIs for CSV file operations. You can build the application w/ LabVIEW in a short time.
You can find the examples of the FBUS APIs in the following folders:
1. C: C:\Program Files\National Instruments\NI-FBUS\MS Visual C\examples
2. VB: C:\Program Files\National Instruments\NI-FBUS\MS Visual Basic\example
3. C#: C:\Program Files\National Instruments\NI-FBUS\MS .NET\examples\CsharpExample
4. LabVIEW: search "fieldbus" in the LabVIEW example finder.

Oracle 11g: Block Corruption in SYSAUX File

Hello All,
I am facing Data corruption issue in the SYSAUX file.
We are using Oracle 11G (Microsoft 32 bit) and our system is running in noarchivelog mode.
Following are the errors in the alert log.
e:\sc\sc15.2\databases\oracleconfig\diag\rdbms\enmscsdb\nm45\trace\nm45_p000_5944.trc
Corrupt block relative dba: 0x0088a9f8 (file 2, block 567800)
Fractured block found during buffer read
Data in bad block:
type: 6 format: 2 rdba: 0x0088a9f8
last change scn: 0x0000.0b3bb7c7 seq: 0x1 flg: 0x04
spare1: 0x0 spare2: 0x0 spare3: 0x0
consistency value in tail: 0xc7000601
check value in block header: 0xee6b
computed block checksum: 0x72c6
Reread of rdba: 0x0088a9f8 (file 2, block 567800) found same corrupted data
Thu Jan 22 16:46:44 2009
SMON: Restarting fast_start parallel rollback
SMON: ignoring slave err,downgrading to serial rollback
ORACLE Instance nm45 (pid = 12) - Error 1578 encountered while recovering transaction (9, 11) on object 458.
Errors in file e:\sc\sc15.2\databases\oracleconfig\diag\rdbms\enmscsdb\nm45\trace\nm45_smon_6492.trc:
ORA-01578: ORACLE data block corrupted (file # 2, block # 567800)
ORA-01110: data file 2: 'E:\SC\SC15.2\DATABASES\ORACLECONFIG\SYSAUXNM45.ORA'
Thu Jan 22 16:46:45 2009
Trace dumping is performing id=[cdmp_20090122164645]
Corrupt Block Found
TSN = 1, TSNAME = SYSAUX
RFN = 2, BLK = 567800, RDBA = 8956408
OBJN = 458, OBJD = 458, OBJECT = I_WRI$_OPTSTAT_HH_OBJ_ICOL_ST, SUBOBJECT =
SEGMENT OWNER = SYS, SEGMENT TYPE = Index Segment
Following query indicates the corruption is in index.
SQL> SELECT tablespace_name, segment_type, owner, segment_name FROM dba_extents
WHERE file_id = 2 and 567800 between block_id AND block_id + blocks - 1;
TABLESPACE_NAME SEGMENT_TYPE OWNER
SEGMENT_NAME
SYSAUX INDEX SYS
I_WRI$_OPTSTAT_HH_OBJ_ICOL_ST
==============
DBverify output:
==============
E:\SC\SC15.2\Databases\OracleConfig>dbv file=SYSAUXNM45.ORA blocksize=8192
DBVERIFY: Release 11.1.0.7.0 - Production on Thu Jan 22 16:59:11 2009
Copyright (c) 1982, 2007, Oracle. All rights reserved.
DBVERIFY - Verification starting : FILE = E:\SC\SC15.2\Databases\OracleConfig/SY
SAUXNM45.ORA
DBV-00200: Block, DBA 8956312, already marked corrupt
Page 567800 is influx - most likely media corrupt
Corrupt block relative dba: 0x0088a9f8 (file 2, block 567800)
Fractured block found during dbv:
Data in bad block:
type: 6 format: 2 rdba: 0x0088a9f8
last change scn: 0x0000.0b3bb7c7 seq: 0x1 flg: 0x04
spare1: 0x0 spare2: 0x0 spare3: 0x0
consistency value in tail: 0xc7000601
check value in block header: 0xee6b
computed block checksum: 0x72c6
DBVERIFY - Verification complete
Total Pages Examined : 1623864
Total Pages Processed (Data) : 540984
Total Pages Failing (Data) : 0
Total Pages Processed (Index): 964944
Total Pages Failing (Index): 0
Total Pages Processed (Other): 17849
Total Pages Processed (Seg) : 0
Total Pages Failing (Seg) : 0
Total Pages Empty : 100086
Total Pages Marked Corrupt : 2
Total Pages Influx : 1
Total Pages Encrypted : 0
Highest block SCN : 190789648 (0.190789648)
SQL> select * from v$database_block_corruption;
FILE# BLOCK# BLOCKS CORRUPTION_CHANGE# CORRUPTIO
2 567800 1 0 FRACTURED
2 567704 1 0 FRACTURED
How to resolve this issue.
Thanks
With Regards
Hemant Joshi.

Drop and re-creating the index would be better than re-building the index.
Check the metalink note: Identify the corruption extension using RMAN/DBV/ANALYZE etc - 836658.1
Note 28814.1 - Handling Oracle Block Corruptions in Oracle7/8/8i/9i/10g
Note 472231.1 - How to identify all the Corrupted Objects in the Database reported by RMAN
ORA-1578 Main Reference Index for Solutions -830997.1

Need advice on ORA-01578: ORACLE data block corrupted

We have a development database server version- 10.2.0.3 with materialized views refresh as complete every morning. Yesterday we had a power failure and the server went down and database was shutdown unexpectedly.
When we restarted the database after the server restarted, we found some of the datablocks got corrupted . Following were the exceptions that we saw in the alert.log.
Errors in file /i01_01/app/oracle/product/10.2.0/db_1/admin/orcl9/bdump/orcl9_smon_7547.trc:
ORA-01578: ORACLE data block corrupted (file # 11, block # 257712)
ORA-01110: data file 11: '/i01_01/app/oracle/product/10.2.0/oradata/orcl9/ts_gen_data_02.dbf'
ORACLE Instance orcl9 (pid = 8) - Error 1578 encountered while recovering transaction (9, 38) on object 54463
I tried the following query to see the segment type.
select owner, segment_name, segment_type from dba_extents where file_id =11 and 257712 between block_id and block_id + blocks - 1;
OWNER
SEGMENT_NAME
SEGMENT_TYPE
VISH
INVENTORY_TXN
TABLE
where " INVENTORY_TXN " is a materialized view that was using the block that got corrupted. I can always recreate the MV by dropping and recreating it. Will it solve the problem???
If not, how can I recover/repair the block.???
Can anyone advice on this. Thanks very much in advance.

To recover a corrupted block,the best way out is to use Blockrecover command of RMAN. So you would need RmAN backup to perform the operation.But first ypu you need to ensure that this is a persistent error or not? Is this error is coming repeatedly or just once it happened?
About Blockrecover command,read here,
http://download.oracle.com/docs/cd/B19306_01/backup.102/b14191/rcmrecov005.htm#BRADV157
HTH
Aman....

BLOCK CORRUPTION (ORA-1578) 처리 (ORACLE 8I NEW FEATURE)

제품 : ORACLE SERVER
작성날짜 : 2002-05-31
BLOCK CORRUPTION (ORA-1578) 처리 (ORACLE 8I NEW FEATURE)
========================================================
PURPOSE
Block Corruption의 처리 방안에 대해 알아본다.
Problem Description
block corruption 시 10210, 10211,10231 의 event 를 사용해서
해당 block 을 skip 할 수도 있지만 V8.1 이상에서는
dbms_repair.fix_corrupt_blocks ,
dbms_repair.skip_corrupt_block 를 이용하여
corrupt가 발생한 block을 detect하고 skip, 또는 repair해주는 방안이
제시되고 있다.
Workaround
Solution Description
- 먼저 detecting 을 위해 db_block_checking =true 를 init.ora 에 set
- dbms_repair 의 package 를 사용하는데 이 package 는 dbmsrpr.sql,
prvtrpr.plb를 수행한다 .
- sys 로 접속하여 package 를 실행한다.
다음의 예제를 살펴보자
T1 테이블에 corrupt 된 block 이 있다고 가정한다.
SQL> desc t1
Name Null? Type
COL1 NOT NULL NUMBER(38)
COL2 CHAR(512)
SQL> analyze table t1 validate structure;
analyze table t1 validate structure
ERROR at line 1:
ORA-01498: block check failure - see trace file
이때 ANALYZE로 부터 발생된 trace file 에 corrupt 된 block 에 3 row 의
(nrows = 3) data 가 있음을 알수 있다고 가정하자.
DBMS_REPAIR.ADMIN_TABLES (repair and orphan key)
================================================
ADMIN_TABLES 은 table 을 위한 repair table과,인덱스를 위한 orphan key
tables을 제공한다.
SQL> @adminCreate
SQL> connect sys/change_on_install
Connected.
SQL>
SQL> -- Repair Table
SQL>
SQL> declare
2 begin
3 -- Create repair table
4 dbms_repair.admin_tables (
5 -- table_name => 'REPAIR_TABLE',
6 table_type => dbms_repair.repair_table,
7 action => dbms_repair.create_action,
8 tablespace => 'USERS'); -- default TS of SYS if not specified
9 end;
10 /
PL/SQL procedure successfully completed.
SQL> select owner, object_name, object_type
2 from dba_objects
3 where object_name like '%REPAIR_TABLE';
OWNER OBJECT_NAME OBJECT_TYPE
SYS DBA_REPAIR_TABLE VIEW
SYS REPAIR_TABLE TABLE
SQL>
SQL> -- Orphan Key Table
SQL>
SQL> declare
2 begin
3 -- Create orphan key table
4 dbms_repair.admin_tables (
5 table_type => dbms_repair.orphan_table,
6 action => dbms_repair.create_action,
7 tablespace => 'USERS'); -- default TS of SYS if not specified
8 end;
9 /
PL/SQL procedure successfully completed.
SQL> select owner, object_name, object_type
2 from dba_objects
3 where object_name like '%ORPHAN_KEY_TABLE';
OWNER OBJECT_NAME OBJECT_TYPE
SYS DBA_ORPHAN_KEY_TABLE VIEW
SYS ORPHAN_KEY_TABLE TABLE
DBMS_REPAIR.CHECK_OBJECT
=========================
CHECK_OBJECT procedure 는 기술된 object를 check 하고, repair 를 위한 정보를 수집하기 위함이다.
SQL> @checkObject
SQL> set serveroutput on
SQL>
SQL> declare
2 rpr_count int;
3 begin
4 rpr_count := 0;
5 dbms_repair.check_object (
6 schema_name => 'SYSTEM',
7 object_name => 'T1',
8 repair_table_name => 'REPAIR_TABLE',
9 corrupt_count => rpr_count);
10 dbms_output.put_line('repair count: ' || to_char(rpr_count));
11 end;
12 /
repair count: 1
PL/SQL procedure successfully completed.
SQL> desc repair_table
Name Null? Type
OBJECT_ID NOT NULL NUMBER
TABLESPACE_ID NOT NULL NUMBER
RELATIVE_FILE_ID NOT NULL NUMBER
BLOCK_ID NOT NULL NUMBER
CORRUPT_TYPE NOT NULL NUMBER
SCHEMA_NAME NOT NULL VARCHAR2(30)
OBJECT_NAME NOT NULL VARCHAR2(30)
BASEOBJECT_NAME VARCHAR2(30)
PARTITION_NAME VARCHAR2(30)
CORRUPT_DESCRIPTION VARCHAR2(2000)
REPAIR_DESCRIPTION VARCHAR2(200)
MARKED_CORRUPT NOT NULL VARCHAR2(10)
CHECK_TIMESTAMP NOT NULL DATE
FIX_TIMESTAMP DATE
REFORMAT_TIMESTAMP DATE
SQL> select object_name, block_id, corrupt_type, marked_corrupt,
2 corrupt_description, repair_description
3 from repair_table;
OBJECT_NAME BLOCK_ID CORRUPT_TYPE MARKED_COR
CORRUPT_DESCRIPTION
REPAIR_DESCRIPTION
T1 3 1 FALSE
kdbchk: row locked by non-existent transaction
table=0 slot=0
lockid=32 ktbbhitc=1
mark block software corrupt
Data Extraction
===============
repair table에 의하면 file 6 ,block 3 에 corrupt 이 났음을 알수 있다
그러나 아직 이 block 은 corrupt 로 mark 되어 있지 않으므로 필요 data 를
추출하여야 한다.
1. ALTER SYSTEM DUMP (nrows = 3) 에 의해 block안에 있는 row수를 결정한다.
2. corrupt object를 select 하여 가능한 정보를 추출한다.
SQL> -- The following query can be used to salvage data from a corrupt block.
SQL> -- Creating a temporary table facilitates data insertion.
SQL> create table temp_t1 as
2 select * from system.t1
3 where dbms_rowid.rowid_block_number(rowid) = 3
4 and dbms_rowid.rowid_to_absolute_fno (rowid, 'SYSTEM','T1') = 6;
Table created.
SQL> select col1 from temp_t1;
COL1
2
3
DBMS_REPAIR.FIX_CORRUPT_BLOCKS (ORA-1578)
============================================
FIX_CORRUPT_BLOCKS procedure는 repair table 의 정보를 이용하여 corrupt
blocks 을 fix 한다
그러나 아직 full table scan 시 여전히 error 가 발생한다
SQL> declare
2 fix_count int;
3 begin
4 fix_count := 0;
5 dbms_repair.fix_corrupt_blocks (
6 schema_name => 'SYSTEM',
7 object_name => 'T1',
8 object_type => dbms_repair.table_object,
9 repair_table_name => 'REPAIR_TABLE',
10 fix_count => fix_count);
11 dbms_output.put_line('fix count: ' || to_char(fix_count));
12 end;
13 /
fix count: 1
PL/SQL procedure successfully completed.
SQL> select object_name, block_id, marked_corrupt
2 from repair_table;
OBJECT_NAME BLOCK_ID MARKED_COR
T1 3 TRUE
SQL> select * from system.t1;
select * from system.t1
ERROR at line 1:
ORA-01578: ORACLE data block corrupted (file # 6, block # 3)
ORA-01110: data file 6: '/tmp/ts_corrupt.dbf'
DBMS_REPAIR.DUMP_ORPHAN_KEYS
==============================
DUMP_ORPHAN_KEYS는 corrupt data 에 해당하는 index 를 나타내 준다
SQL> select index_name from dba_indexes
2 where table_name in (select distinct object_name from repair_table);
INDEX_NAME
T1_PK
SQL> @dumpOrphanKeys
SQL> set serveroutput on
SQL>
SQL> declare
2 key_count int;
3 begin
4 key_count := 0;
5 dbms_repair.dump_orphan_keys (
6 schema_name => 'SYSTEM',
7 object_name => 'T1_PK',
8 object_type => dbms_repair.index_object,
9 repair_table_name => 'REPAIR_TABLE',
10 orphan_table_name => 'ORPHAN_KEY_TABLE',
11 key_count => key_count);
12 dbms_output.put_line('orphan key count: ' || to_char(key_count));
13 end;
14 /
orphan key count: 3
PL/SQL procedure successfully completed.
SQL> desc orphan_key_table
Name Null? Type
SCHEMA_NAME NOT NULL VARCHAR2(30)
INDEX_NAME NOT NULL VARCHAR2(30)
IPART_NAME VARCHAR2(30)
INDEX_ID NOT NULL NUMBER
TABLE_NAME NOT NULL VARCHAR2(30)
PART_NAME VARCHAR2(30)
TABLE_ID NOT NULL NUMBER
KEYROWID NOT NULL ROWID
KEY NOT NULL ROWID
DUMP_TIMESTAMP NOT NULL DATE
SQL> select index_name, count(*) from orphan_key_table
2 group by index_name;
INDEX_NAME COUNT(*)
T1_PK 3
Note: orphan key table의 index 는 다시 rebuild 되어야 한다.
DBMS_REPAIR.SKIP_CORRUPT_BLOCKS
===============================
SKIP_CORRUPT_BLOCKS 은 table 과 index 의 corrupt block 을 skip 하는 것을 enable/disable 을 실시한다.
Suggestion: SKIP_CORRUPT_BLOCKS 가 enabled되면 orphan key table의 모든
index 는 모두 rebuild 되어야 한다. ( all index associated with object
if DUMP_ORPHAN_KEYS was omitted).
SQL> @skipCorruptBlocks
SQL> declare
2 begin
3 dbms_repair.skip_corrupt_blocks (
4 schema_name => 'SYSTEM',
5 object_name => 'T1',
6 object_type => dbms_repair.table_object,
7 flags => dbms_repair.skip_flag);
8 end;
9 /
PL/SQL procedure successfully completed.
SQL> select table_name, skip_corrupt from dba_tables
2 where table_name = 'T1';
TABLE_NAME SKIP_COR
T1 ENABLED
SQL> -- rows in corrupt block skipped, no errors on full table scan
SQL> select * from system.t1;
COL1 COL2
4 dddd
5 eeee
--> Notice the pk index has not yet been corrected.
SQL> insert into system.t1 values (1,'aaaa');
insert into system.t1 values (1,'aaaa')
SQL> select * from system.t1 where col1 = 1;
no rows selected
DBMS_REPAIR.REBUILD_FREELISTS
===============================
REBUILD_FREELISTS rebuilds freelists for the specified object.
SQL> declare
2 begin
3 dbms_repair.rebuild_freelists (
4 schema_name => 'SYSTEM',
5 object_name => 'T1',
6 object_type => dbms_repair.table_object);
7 end;
8 /
PL/SQL procedure successfully completed.
Rebuild Index
=============
Note: Every index identified in the orphan key table should be rebuilt to
ensure consistent results.
SQL> alter index system.t1_pk rebuild online;
Index altered.
SQL> insert into system.t1 values (1, 'aaaa');
1 row created.
SQL> select * from system.t1;
COL1 COL2
4 dddd
5 eeee
1 aaaa
Reference Document
------------------

Try look to alert<SID>.log file for full error report (you could paste it here).
Also from alert log you could get real values for db_block_buffers and shared_pool_size parameters that used during instance startup.

Diff between logical and physical block corruption

What is the difference between Physical and Logical block corruption.
Dbverify utility, analyze command is used to check the logical block corruption not the physical one am i correct??
When i get
ORA-01578: ORACLE data block corrupted (file # 9, block # 13)
ORA-01110: data file 9: '/oracle/dbs/tbs_91.f'
ORA-01578: ORACLE data block corrupted (file # 2, block # 19)
ORA-01110: data file 2: '/oracle/dbs/tbs_21.f'
How to conform that this a logical or physical block corruption???
please through some light regarding this....
kumaresh

the following link may help u
http://download-east.oracle.com/docs/cd/B19306_01/backup.102/b14191/rcmconc1012.htm

System datafile block corruption - no backups and database in NOARCHIVELOG mode

Dear All,
Database version - oracle 11.1 Enterprise
OS - RHELinux 5.8
What are the options of recovering from physical block corruption when there are no backup available to perform block media recovery?
V$DATABASE_BLOCK_CORRUPTION reports two segments corrupted (please see attached image for details).
1 table in system datafile - sys_fba_barrierscn
1 index - (applicaiton index)
What are my options?
I know there is a possibility that the database will not restart after a shutdown due to corruption in system tablespace.
Database is in noarchivelog mode. So online backups are not possible and there aren't any full backups either.
I am thinking of below,
1. Run dbms_repair with fix_block_corruption. - Still database startup might fail?
2. Shutdown the database and take offline full backup with RMAN MAXCorrupt option.
Appreciate your suggestions and advises.
Thanks
Stefan

Thanks Sybrand,
Agree with your first two suggestions .
Also scheduled a expdp job tonight. (Only backup like thing they had was a expdp cron, but until today all the large tables were failing due to small undo_retention).
Yes. Flashback is not used. So hopefully it will not affect the a database restart i guess?
Related to dbms_repair, I was referring to - http://askdba.org/weblog/2010/08/physical-corruption-ora-1578-part-3/.
Where DBMS_REPAIR.FIX_CORRUPT_BLOCKS and DBMS_REPAIR.SKIP_CORRUPT_BLOCKS used.
Which i think will not use any redo.
Thanks
Stefan

How to create a feedback control system in labview with an integration block?

Hallo,
I design a model of a simple mechanic system composed by one damper, one mass and one spring.
I would simulate a free response of this mechanic system, but I don't be able to integrate the mechanic state in Labview.
Seeming that the integration block in LabView produce a wrong answer.
I've attached this model create in Labview 8.2.1.
Thanks in Advance
Michele
Attachments:
Sistema dinamico6.vi ‏462 KB

Michele,
First of all, when you are trying to develop a Dynamic Simulation, I strongly recommend that you use the LabVIEW Control Design and Simulation Module (http://sine.ni.com/nips/cds/view/p/lang/en/nid/203826), or, for LabVIEW 8.2.1, the LabVIEW Simulation Module. They allow you to develop your dynamic simulation natively in LabVIEW, specially in the case that you have feedback loop in your code (which is your case).
Now, looking at your program, I have several recommendations that would help you to better control your simulation. First, avoid using the Dynamic Datatype (Blue wire) in you simulation. For example, you are generating a Waveform inside the loop and you are just getting one element of the first batch. Probably, you want to generate only one element per iteration of the while loop and apply that to your equation. If that is the case, you should remove the "Simulation Signal" express VI and use the Point-by-point VI (located at Signal Processing Pallette). There you can also find an integration VI that allow you to define the sampling time for your application.
Also, the feedback node that you are using will introduce one sampling time to your simulation, which mean that, if your simulation and equations are not correctly setup to take that into account, your simulation will be incorrect. If you were using the Simulation Module, it would take care for your to do the correct integration, additional to allow using different solvers (like RK 4-5) to reduce the error on the integration.
Hope this helps. Let me know if you have more questions.
Barp - Control and Simulation Group - LabVIEW R&D - National Instruments

Oracle 11g - How to repair block corruption(on free space) in datafile

Hi,
I have a tablesopace with 3 datafiles, out of which one datafile has corrupted block. But no objects or data is affected as the corrupted block os in free space. This was shown in the alert logs.
Please see below the details:
Wed Apr 06 15:30:04 2011
SMON: Restarting fast_start parallel rollback
SMON: ignoring slave err,downgrading to serial rollback
ORACLE Instance geooap (pid = 12) - Error 1578 encountered while recovering transaction (10, 6) on object 149755.
Errors in file f:\oracle11g\diag\rdbms\geooap\geooap\trace\geooap_smon_5540.trc:
ORA-01578: ORACLE data block corrupted (file # 7, block # 54053)
ORA-01110: data file 7: 'F:\ORACLE11G\ORADATA\GEOOAP\ORDER_DATA_01.DBF'
GEOAP:
Fri Apr 01 14:57:48 2011
Errors in file f:\oracle11g\diag\rdbms\geop\geop\trace\geop_arc1_2156.trc:
ORA-00235: control file read without a lock inconsistent due to concurrent update
Fri Apr 01 14:57:58 2011
================================================================
The corruption is being reported in a free space block of the ORDER_DATA_01.DBF.
I’ve checked all the tables (and indexes) in this tablespace and none report corruption.
=====================================================Is there any action I need to take to remove corruption at this point?It is not affected any operation on the database yet.
What is the best way to do get rid of the corrupt block, without dropping and rebuillding the full tablespace(which is around 6 GB -total of 3 datafiles)
Thanks a lot

Can RMAN recover the datablock from this cold backup(which is a week old, the data file was not corrupted then) ?Please note that to do the recovery, you would need the backup and the archivelog files since the backup. Think about what you are asking to do. Its a single block whose recovery you are asking from a week old backup which obviously would be on an much older SCN compared to the rest of the database. How would you make that block consistent with the rest of the datafile. If you don't have archivelog in that db whose block is corrupted, you may forget that block and any data that it might ever had. Also, please read the documentation about the block recovery which explains the requirements very clearly,
http://download.oracle.com/docs/cd/E11882_01/backup.112/e10642/rcmblock.htm#BRADV89784
From the above link, 1st point,
The target database must run in ARCHIVELOG mode and be open or mounted with a current control file.HTH
Aman....

Data Block Corruption

I'm on 9i R2 Patch 7 on a Microsoft Windows Server 2003.
How do you fix data block corruption in a Table?
Is the some way to retrieve the data from the Table drop it then recreate and reimport the data?
or do you have to succumb with restoring the Database from the last known good backup?

Hey, you can do the BMR (Block Media Recovery).
Since block corruption is to few subsets of blocks, i.e. a single table, you dont need to restore from the previous valid backup, you can simply do the following to achieve BMR.
Connect to rman and run the following:
run{ backup validate database};
Once the above commend is finishes, exit from RMAN and connect to the database as / as sysdba and use the following view to know the details required for BMR.
select * from V$backup_corruption;
The above queries gives you file# and block# information. Once you have the information do the BMR using following command at the RMAN prompt:
run {blockrecover datafile # block #};
# : indicated the datafile number and block number from the above view.
Let me know if you have any further issues.
You can also use view V$DATABASE_BLOCK_CORRUPTION to view the file# and corrupted blocks information.
Jaffar

Finding and fixing block corruption in oracle 10g

10.2.0.5.6
OS: Hp-unix
databases files on RAW.
DB Size: 10 TBs+
We had a SAN outage recently. The DB is back online. We want to check for block corruption to be on the safe side. We are planning to take a SAN EMC BCV copy of prod to run this. Looking for opinioms on the best way.Production is up and running. This is just a sanity check.
We are NOT using RMAN for backups. We do a BCV copy and then back that up and archive logs to tape.
RMAN: Can we do this from the control files? Do we have to set anything up? Is this the best way?
DBMS_REPAIR: I have not used this. We don't even have the package installed. I can install it.
DB_VERIFY: not sure if this is a good option or not. Is this current? I know I'll have to do it file by file and grep the logs. I have used this in the past, but its been a while.
Performance issues, CPU, I/O don't matter. We are doing a BCV copy and then mounting the DB on a new server.

Guess2 wrote:
10.2.0.5.6
OS: Hp-unix
databases files on RAW.
DB Size: 10 TBs+
We had a SAN outage recently. The DB is back online. We want to check for block corruption to be on the safe side. We are planning to take a SAN EMC BCV copy of prod to run this. Looking for opinioms on the best way.Production is up and running. This is just a sanity check.
We are NOT using RMAN for backups. We do a BCV copy and then back that up and archive logs to tape.
RMAN: Can we do this from the control files? Do we have to set anything up? Is this the best way?
DBMS_REPAIR: I have not used this. We don't even have the package installed. I can install it.
DB_VERIFY: not sure if this is a good option or not. Is this current? I know I'll have to do it file by file and grep the logs. I have used this in the past, but its been a while.
Performance issues, CPU, I/O don't matter. We are doing a BCV copy and then mounting the DB on a new server.
bcm@bcm-laptop:~$ dbv -help
DBVERIFY: Release 11.2.0.1.0 - Production on Mon May 21 07:29:42 2012
Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved.
Keyword     Description                    (Default)
FILE        File to Verify                 (NONE)
START       Start Block                    (First Block of File)
END         End Block                      (Last Block of File)
BLOCKSIZE   Logical Block Size             (8192)
LOGFILE     Output Log                     (NONE)
FEEDBACK    Display Progress               (0)
PARFILE     Parameter File                 (NONE)
USERID      Username/Password              (NONE)
SEGMENT_ID Segment ID (tsn.relfile.block) (NONE)
HIGH_SCN    Highest Block SCN To Verify    (NONE)
            (scn_wrap.scn_base OR scn)           can be done against any datafile; open or closed, production or clone
Handle:     Guess2
Status Level:     Newbie
Registered:     Aug 5, 2000
Total Posts:     454
Total Questions:     212 (201 unresolved)
WHY so MANY unanswered questions?
Edited by: sb92075 on May 21, 2012 7:31 AM

Monitor db integrity / block corruption

Similar Messages

Maybe you are looking for