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

Similar Messages

How to check & resolve block corruption if no RMAN backup is there?

*<<+MY Findings+>>*
to check block corruption :
(run command)
select * from v$database_block_corruption;
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 check block corruption
DBVerify
C:\>dbv userid=nfadmin/nfadmin file=+DG1/nfdb/datafile/low_s_data.304.782536883 feedback=10000 blocksize=8192
can use DBMS_REPAIR to detect and repair corrupt blocks in tables and indexes
BEGIN
DBMS_REPAIR.admin_tables (
table_name => 'REPAIR_TABLE',
table_type => DBMS_REPAIR.repair_table,
action => DBMS_REPAIR.create_action,
tablespace => 'USERS');
DBMS_REPAIR.admin_tables (
table_name => 'ORPHAN_KEY_TABLE',
table_type => DBMS_REPAIR.orphan_table,
action => DBMS_REPAIR.create_action,
tablespace => 'USERS');
END;
Question* :::how to check & resolve block corruption if no RMAN backup is there?

http://www.oracle.com/technetwork/database/focus-areas/availability/maa-datacorruption-bestpractices-396464.pdf
http://www.oracle-base.com/articles/misc/detect-and-correct-corruption.php

Block corruption detection in RMAN.

Hi,
I'd be be grateful if anyone could confirm or clarify the behaviour of the RMAN backup command with regard to detecting corrupt blocks in the datafiles.
The environment is as follows:
10.2.0.5.1
Solaris 10
2 node RAC
Block Change Tracking file is not used.
DB_BLOCK_CHECKING=OFF
DB_BLOCK_CHECKSUM=OFF
Does the BACKUP DATABASE command check both physical and logical block corruptions when run either as a full backup or incremental?
I'm trying to establish wether running a BACKUP _VALIDATE [CHECK LOGICAL]_* DATABASE on a nightly basis provides any value if the same checks are being performed by the standard backup commands that are already scheduled every night?
Any input appreciated.
Thanks

Hi,
By default, RMAN just check for physical corruption, either in full or incremental backups. To check logical corruption you have to use the command "backup check logical;".
About the parameter DB_BLOCK_CHECKSUM, its default is TRUE and Oracle Corporation advises leaving this parameter on default, so that any damage caused while the block is on disk, or corruptions introduced during the write and read process, will be detected.
Hope it help.
Regards,

Logical block corruption in an unused block which is a part of index

Hi All,
During RMAN backup level 0 I am getting a corrupted block my DB:
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03009: failure of backup command on t20 channel at 07/22/2009 21:30:49
ORA-19566: exceeded limit of 0 corrupt blocks for file /oracle/oradata/DB2/plind05_02.dbf
SQL> select * from v$database_block_corruption;
FILE# BLOCK# BLOCKS CORRUPTION_CHANGE# CORRUPTIO
2950 1879477 1 1.0124E+13 LOGICAL
SQL> SELECT tablespace_name, partition_name,segment_type, owner, segment_name FROM dba_extents WHERE file_id = 2950 and 1879477 between block_id AND block_id + blocks - 1;
no rows selected
So this block does not belong to any object.
SQL > select * from dba_free_space where file_id= 2950 and 1879477 between block_id and block_id blocks -1;+
TABLESPACE_NAME FILE_ID BLOCK_ID BYTES BLOCKS RELATIVE_FNO
USAGIDX_200907 2950 1879433 1048576 128 909
But it exists in dba_free_space so it belongs to file space usage bitmap.
DB Verify shows:
myserver:/oracle/rman/DB2:DBINST1> dbv file=/oracle/oradata/DB2/plind05_02.dbf BLOCKSIZE=8192
DBVERIFY: Release 10.2.0.4.0 - Production on Wed Jul 29 13:47:38 2009
Copyright (c) 1982, 2007, Oracle. All rights reserved.
DBVERIFY - Verification starting : FILE = /oracle/oradata/DB2/plind05_02.dbf
Block Checking: DBA = -480465494, Block Type = KTB-managed data block
**** row 2: key out of order
---- end index block validation
Page 1879477 failed with check code 6401
DBVERIFY - Verification complete
Total Pages Examined : 4194176
Total Pages Processed (Data) : 0
Total Pages Failing (Data) : 0
Total Pages Processed (Index): 3404935
Total Pages Failing (Index): 1
Total Pages Processed (Other): 569
Total Pages Processed (Seg) : 0
Total Pages Failing (Seg) : 0
Total Pages Empty : 788672
Total Pages Marked Corrupt : 0
Total Pages Influx : 0
Highest block SCN : 1795222745 (2360.1795222745)
Now, I have identified that this block belongs to an index subpartition so I have rebuild it with alter index ... rebuild subpartition... However, the RMAN backup still fails and DBV still reports an error.
I know that we could simply recreate the index but the problem is that its quite big (>6GB and table is >7TB).
My strong feeling is that the cause of this is that corrupted blocks will still be reported by RMAN and DBV until they are reused and reformatted.
My question is:
How can I reuse or reformat a block which does not belong to any object?

Hi,
Yes you're right, you need to reformat that block.
For that you need to allocate that block to a table, and fill that table with data until high water mark goes higher than block 1879477.
This isthe way I've done it once:
1) check the free space size below that block:
select sum(bytes)/1024/1024 before from dba_free_space where file_id=1879477 and block_id <= 1503738;
Let's say it is 6000 MB
2) create a dummy table, allocate enough extents to fill the size returned from the previous query
This does not format blocks, but the advantage of allocate extents is that you can specify size and datafile:
alter table allocate extents size 6000M datafile '/oracle/oradata/DB2/plind05_02.dbf';
you can check dba_extents to see if it covers block 1879477. If not, try to add a little more extents.
3) fill the table with data to fill those extents.
One idea is to insert one rows into the table, then use 'alter table test minimize records_per_block;' so that each block will have 2 rows maximum.
check the number of blocks (from dba_segments). Say you have 768000 blocks. Then you need to insert 768000/2 rows:
insert into ... select ... from dual connect by level < (768000/2)
4) check the high water mark has reach the end of all extents (compare dba_tables.blocks and dba_segemnts.blocks)
5) if not enough, try to add a little more rows.
Be careful that you don't go too far (especially if you have extensible datafile). Unfortunately, maxextents is ignored on LMT :(
6) now, your block should be reformatted. Just drop the dummy table.
Regards,
Franck.

Block corruption - cant restore from backup

Hi,
we have development database 11.2.0.1. There was problem with storage, and as a result there are two corrupted blocks in data files.
SQL> select * from V$DATABASE_BLOCK_CORRUPTION;
FILE# BLOCK# BLOCKS CORRUPTION_CHANGE# CORRUPTIO
6 2359942 1 0 FRACTURED
25 1855622 1 0 FRACTURED
I have scheduled weekly full backup and daily incremental backup using EM so now I want to use rman to perform media recovery on corrupted blocks. However rman says there is no backup for affected data files (see below)
RMAN> RECOVER CORRUPTION LIST;
Starting recover at 03-NOV-12
using channel ORA_DISK_1
using channel ORA_DISK_2
using channel ORA_DISK_3
using channel ORA_DISK_4
using channel ORA_DISK_5
channel ORA_DISK_1: restoring block(s)
channel ORA_DISK_1: specifying block(s) to restore from backup set
restoring blocks of datafile 00006
channel ORA_DISK_1: reading from backup piece /opt/oraBackup/rman/i2npb3o9_1_1
channel ORA_DISK_1: piece handle=/opt/oraBackup/rman/i2npb3o9_1_1 tag=BACKUP_FULL_110212103009
channel ORA_DISK_1: restored block(s) from backup piece 1
channel ORA_DISK_1: block restore complete, elapsed time: 00:42:35
channel ORA_DISK_1: restoring block(s)
channel ORA_DISK_1: specifying block(s) to restore from backup set
restoring blocks of datafile 00025
channel ORA_DISK_1: reading from backup piece /opt/oraBackup/rman/i9npbd5e_1_1
channel ORA_DISK_1: piece handle=/opt/oraBackup/rman/i9npbd5e_1_1 tag=BACKUP_FULL_110212103009
channel ORA_DISK_1: restored block(s) from backup piece 1
channel ORA_DISK_1: block restore complete, elapsed time: 00:16:35
failover to previous backup
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of recover command at 11/03/2012 11:59:29
RMAN-06026: some targets not found - aborting restore
RMAN-06023: no backup or copy of datafile 25 found to restore
RMAN-06023: no backup or copy of datafile 6 found to restore
I dont understand this, because the backups are performed weekly and daily and all files are at their proper location. When I check the EM backup reports, I see COMPLETED for every weekly and daily backup.
Anyone please could suggest how to repair the blocks from backups ?

Hi people, I am back to this issue. I have found this in the database
SQL> select * from v$backup_corruption;
     RECID      STAMP SET_STAMP SET_COUNT     PIECE#      FILE#     BLOCK#     BLOCKS CORRUPTION_CHANGE# MAR CORRUPTIO
         1 796949262 796948233       9293          1          6    2359942          1                  0 NO CORRUPT
         2 796953328 796949174       9300          1         25    1855622          1                  0 NO CORRUPT
         3 797035604 797034635       9318          1          6    2359942          1                  0 NO CORRUPT
         4 797039692 797035556       9325          1         25    1855622          1                  0 NO CORRUPT
         5 797134390 797121030       9343          1          6    2359942          1                  0 NO CORRUPT
         6 797137228 797134397       9368          1         25    1855622          1                  0 NO CORRUPT
         7 797739951 797725854       9590          1          6    2359942          1                  0 NO CORRUPT
         8 797744507 797739957       9597          1         25    1855622          1                  0 NO CORRUPT
         9 798340269 798330633       9794          1          6    2359942          1                  0 NO CORRUPT
        10 798343497 798340270       9801          1         25    1855622          1                  0 NO CORRUPTSo the backup contains corrupted blocks. Right ? Older backups are already gone because of retention policy.
I have set up the backup using Enterprise Manager - Schedule Backup.
What I need to know is how to avoid taking backup with corrupted blocks in future. I need such backup to fail.
Thank you for advices and regards.

Logical block corruption

Hi all,
i have database 11.2.0.1.0 on linux 5. on this database we found so many block corruption with are related to indexes.
some of the indexes rebuiled, and rebuilded indexes are working fine. But we have so many indexes corrupted.
SQL> select count(*) from v$database_block_corruption;
COUNT(*)
2347
SQL>
i verified by from RMAN logical check also.
if i keep on rebuilding these indexes it will take long time and maily may impact on performance.
Could you please suggest what is the best possible ways to get out from this.
thanks a lot.

899329 wrote:
Hi all,
i have database 11.2.0.1.0 on linux 5. on this database we found so many block corruption with are related to indexes.
some of the indexes rebuiled, and rebuilded indexes are working fine. But we have so many indexes corrupted.
SQL> select count(*) from v$database_block_corruption;
COUNT(*)
2347
SQL>
i verified by from RMAN logical check also.
if i keep on rebuilding these indexes it will take long time and maily may impact on performance.
Could you please suggest what is the best possible ways to get out from this.
thanks a lot.Replace the sick disk.

Why is Pfile not in RMAN - backup

RMAN backups spfile together with controlfile. Why doesn't it support backing up pfile? Is is possible to configure it as to backup pfile too?
Thx.
Aliq.
Message was edited by:
user547746

pfiles are obsolete, and you should stop using them.Incorrect ,obsolete means not usable but one can use it and one using it,you can say its not recommended,on the basis of human readable pfile you created spfile .
Before spfile , pfile commented parameter mess the DBA when and what for used this parameter ,though DBA used comments by providing date and if it happens to change 20 times then he has to make comments 20 times ,with the invent of spfile you can save yours own pfile with dated version within filename i.e (initORCL15042008.ora) and then create the spfile from this pfile ,now you can maitnin yours pfile history easily as before.You can track when and what was changed.You can revert back to yours current instance as old one by creating spfile from oldpfile.
To OP
spfile is for single source of server parameters which is fact, thats why RMAN take spfile backup rather pfile.
You can also change some dynamic parameter during instance working ,you can change it in the spfile as well within instance memory.
Khurram

Not enough icloud backup storage for iphone 5 64GB

It would seem that someone has dropped the ball with regards to icloud backup for iphone 5 64GB. icloud only offers 55 GB of storage. My complaint is obviously redundant!

Hi Buddhathoughts,
The reason that Apple only goes up to that much storage is that some of the items on your device don't count against the icloud storage. Here is a quote from Apple's icloud description. " And that’s plenty of room, because of the way iCloud stores your content. Your purchased music, movies, apps, books, and TV shows — as well as your Photo Stream — don’t count against your free storage. That 5GB goes a long way for your mail, documents, account information, settings, and other app data."
So if you have purchased 10GB of Tv shows, that 10GB will not count against your icloud storage. Also, with photos and videos. The photos and videos in your camera roll will count against your storage. But the photos(videos are not in the photo stream) in your photo stream will not count against your storage.
I hope that answered your question.

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

Rman Detect Block Corruption

Hi
I know rman detect block corruption but my question is block corruption having two types one is physical block corruption and other is logical block corruption
by default rman enable physical block corruption but by default rman not able to detect logical block corruption.Plz tell how i enable logical block corruption with RMAN?
Please make correction if i m wrong.
Thanks a lot.

>> Sorry i am not telling you i am using oracle 9iR2 instead of oracle 10g
It's okay.
That's why; it's been already told that before posting in the forums, better it's better to specify/mention the Oracle Version/OS Details, etc to get the accurate and response.
>> Send me if you have 9i related document.
No need to send you the related documents, when there is a bulk repository available for free of cost for everybody.
All you need to do is, just search in http://tahiti.oracle.com/ with the required word or phrase.
Don't take me wrong, but make a habit of searching related documents from the Oracle Documentations.
Regards,
Sabdar Syed.

Corrupt logical block

I want to check logical block corruption and repair it with dbms_repair package.
For that first i need to corrupt block logically.
How to corrupt oracle database table block logically? Is there any procedure to do that?
Thanks,

Hello,
Thanks for you resposes.
I tried to corrupt datablock by editing datafile and remove some data and add some data.
1. Execurted below rman commad
RMAN> backup validate check logical database;
Output show block is corrupted.
Below query is also listing corrupted blocks.
SQL> select * from v$database_block_corruption;
But when i am checking corruption with dbms_repair packges it doesn't list any corruption.
SET SERVEROUTPUT ON
DECLARE num_corrupt INT;
BEGIN
num_corrupt := 0;
DBMS_REPAIR.CHECK_OBJECT (
SCHEMA_NAME => 'TEST',
OBJECT_NAME => 'TEST1',
REPAIR_TABLE_NAME => 'REPAIR_TABLE',
CORRUPT_COUNT => num_corrupt);
DBMS_OUTPUT.PUT_LINE('number corrupt: ' || TO_CHAR (num_corrupt));
END;
Please let me know any other scenarios to corrupt LOGICAL block.
Thanks,

How RMAN detect block corruption

Hi,
how RMAN detect block corruption( means how RMAN work internally to find corrupted block).
thanks.

There are initialization parameters (like DB_BLOCK_CHECKING) which will detect block corruption on block access. Go through the following link also:
http://download.oracle.com/docs/cd/B19306_01/backup.102/b14191/rcmconc1.htm

Whats the difference ( RMAN BACKUP)

Please let me know the diffrence between
1.Alter database begin backup
2. backup database
After my own research all i can find is that Alter database begin backup freeeze the SCN and then we can copy the files from OS level
Where backup database directly create backup set ( backup piece) ..
I would like to know the functional differnce between the two if there is any...
Plus ...doing alter database begin backup ...am i not taking care of logical corruption..
Does alter database being backup does not validate or find out the logical corruption before...
I also came know from a OCA that it just puts in backup mode and dont really pay attention to checking or validating the files...before backin up.
Is that true?
Thanks in advance
Max
Edited by: Sunny-ORACLE on Aug 18, 2009 4:59 AM

Sunny-ORACLE wrote:
Please let me know the diffrence between
1.Alter database begin backup
2. backup database
After my own research all i can find is that Alter database begin backup freeeze the SCN and then we can copy the files from OS level
Where backup database directly create backup set ( backup piece) ..
I would the functional differnce between the two if there is any...The backup database doesn't need to freeze any headers as RMAN knows how to read the datafiles of oracle. Its knows them very well. So there is nothing we need in the case of rman to check that when the backup was done.
Plus ...doing alter database begin backup ...am i not taking care of logical corruption..
Does alter database being backup does not validate or find out the logical corruption before...
I came know from a OCA that it just puts in backup mode and dont really pay attention to checking or validating the files...before backin up.
Yes its correct, the commands, alter database begin backup pr backup database doesn't check for any sort of corruptions. Fordoing that, you either need to fire up oS util. DBV for checking the physical corruptions or use RMANs Backup Validate or Backup Validate Check Logical to check for physical/logical corruptions.
HTH
Aman....

Needs help regarding block corruption

DB Version - 11.2.0.3.0
Issue - Last backup failed due to block corruption ,message says "ORA-19566: exceeded limit of 0 corrupt blocks for file /GP/GAA01-N-P/db00/index01/GPEDWPR/bi_gpedw_fcct.dbf'
I tried to perform block recovery using RMAN but it was not present in backup, hence failed. tried in the below way also :-
RMAN> LIST FAILURE
2> ;
using target database control file instead of recovery catalog
List of Database Failures
=========================
Failure ID Priority Status Time Detected Summary
72981 HIGH OPEN 13-JAN-13 Datafile 58: '/GP/GAA01-N-P/db00/index01/GPEDWPR/bi_gpedw_fcct.dbf'
contains one or more corrupt blocks
RMAN> ADVISE FAILURE
2> ;
List of Database Failures
=========================
Failure ID Priority Status Time Detected Summary
72981 HIGH OPEN 13-JAN-13 Datafile 58: '/GP/GAA01-N-P/db00/index01/GPEDWPR/bi_gpedw_fcct..dbf' contains one or more corrupt blocks
analyzing automatic repair options; this may take some time
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=2055 device type=DISK
analyzing automatic repair options complete
Mandatory Manual Actions
========================
1. No backup of block 3106752 in file 58 was found. Drop and re-create the associated object (if possible), or use the DBMS_REPAIR package to repair the block corruption
2. No backup of block 3106911 in file 58 was found. Drop and re-create the associated object (if possible), or use the DBMS_REPAIR package to repair the block corruption
3. No backup of block 3106976 in file 58 was found. Drop and re-create the associated object (if possible), or use the DBMS_REPAIR package to repair the block corruption
4. No backup of block 3107504 in file 58 was found. Drop and re-create the associated object (if possible), or use the DBMS_REPAIR package to repair the block corruption
5. Contact Oracle Support Services if the preceding recommendations cannot be used, or if they do not fix the failures selected for repair
Now how to troubleshoot ? Any help will be highly appreciated

First, you need to determine to which segment the block is assigned:
select segment_type,owner,segment_name
from dba_extents
where file_id=58 and 3106752 between block_id and (blockid + blocks -1);
Your action from there will depend on the type of segment. Since you have no backup, the options are limited. But there are still possibilities.

Block corruption in Free Space

Hi,
Environment:-
Oralce 10.2.0
Windows platform
I am facing problem of Logical block corruption.
RMAN validate block corruption (DBVerify as well) But no entry in Alert log file.
When I check Which segment has block corruption I found that block corruption are in free blocks of tablespace (DBA_FREE_SPACE).
To Fix it I create table and allocate corrupted block to that table. I confirm corrupted block allocation in table (using DBA_EXTENTS).
But when I insert rows in that table to reuse corrupted block Oracle give error of ora-1578 Block corruption, and I am not able to reuse corrupted block(as many expert suggest to overcome block corruption in free space).
I dropped table and recreate and repeat this process many times but still no success.
So. can anybody help me on this.
I appreciate your efforts and time you spend to read this
Thanks

Hello,
Please check the link i posted.
Example: Detecting Corruption
The CHECK_OBJECT procedure checks the specified object, and populates the repair table with information about corruptions and repair directives. You can optionally specify a range, partition name, or subpartition name when you want to check a portion of an object.
Validation consists of checking all blocks in the object that have not previously been marked corrupt. For each block, the transaction and data layer portions are checked for self consistency. During CHECK_OBJECT, if a block is encountered that has a corrupt buffer cache header, then that block is skipped.
The following is an example of executing the CHECK_OBJECT procedure for the scott.dept table.
SET SERVEROUTPUT ON
DECLARE num_corrupt INT;
BEGIN
num_corrupt := 0;
DBMS_REPAIR.CHECK_OBJECT (
SCHEMA_NAME => 'SCOTT',
OBJECT_NAME => 'DEPT',
REPAIR_TABLE_NAME => 'REPAIR_TABLE',
CORRUPT_COUNT => num_corrupt);
DBMS_OUTPUT.PUT_LINE('number corrupt: ' || TO_CHAR (num_corrupt));
END;
SQL*Plus outputs the following line, indicating one corruption:
number corrupt: 1

Logical Block corruption - not enough RMAN backups

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