How do you resolve redo log corruption?

How do you resolve redo log corruption?

If the database is up and redo logs are available you could type RECOVER DATAFILE 2 and hit enter for now. If the database is hung, SHUTDOWN IMMEDIATE then STARTUP MOUNT, then RECOVER DATAFILE 2, then ALTER DATABASE OPEN. RECOVER DATABASE will check and recover all oracle datafiles and is fine too.

How do I manually use redo logs?

To apply the archived redo logs in the archive gap

  1. Start up and mount the standby database (if it is not already mounted).
  2. Recover the database using the AUTOMATIC option:
  3. Cancel recovery after the Oracle database server has applied the available logs, by executing the following statement (or typing CTRL+C):

How do I view a redo log file?

The following query returns the control file information about the redo log for a database. If STATUS is blank for a member, then the file is in use….Redo Log Data Dictionary Views.

View Description
V$LOGFILE Identifies redo log groups and members and member status
V$LOG_HISTORY Contains log history information

What does redo log file do?

Redo entries record data that you can use to reconstruct all changes made to the database, including the undo segments. Therefore, the redo log also protects rollback data.

How do I restore a database using redo logs?

To perform time-based recovery:

  1. Issue the RECOVER DATABASE UNTIL TIME statement to begin time-based recovery.
  2. Apply the necessary redo log files to recover the restored datafiles.
  3. Apply redo logs until the last required redo log has been applied to the restored datafiles.
  4. Open the database in RESETLOGS mode.

How do I drop a redo log in Oracle?

To drop specific inactive redo log members, use the ALTER DATABASE statement with the DROP LOGFILE MEMBER clause. The following statement drops the redo log /oracle/dbs/log3c. rdo : ALTER DATABASE DROP LOGFILE MEMBER ‘/oracle/dbs/log3c.

Can I delete Oracle redo logs?

It is permissible to drop redo log files so that a multiplexed redo log becomes temporarily asymmetric. For example, if you use duplexed groups of redo log files, you can drop one member of one group, even though all other groups have two members each.

How do you multiplex a redo log file?

To multiplex your redo log, you must add members to each redo log group. It is not required that redo log groups be symmetrical, but Oracle recommends that your groups all have the same number of members. A database must have a minimum of two redo log groups.

How do I recreate redo logs in Oracle RAC?

Steps to add redo log groups to Oracle RAC setup

  1. Check existing redo log groups & redo log file size. SQL> column REDOLOG_FILE_NAME format a50; SQL> set lines 1000.
  2. As we checked redo log file location & size, we will proceed for redo log group addtions.
  3. Check for newly added redo log groups:

How do I drop and recreate redo logs in Oracle RAC?

Steps to drop redo log groups

  1. While dropping redo log group & we need to check the status of redo log groups. redo log group status should be INACTIVE or UNUSED.
  2. To drop inactive/unused redo log group: SQL> Alter database drop logfile group 1; Database altered.
  3. Check again to verify the redo log groups:

How do I drop and recreate redo logs in standby database?

How to drop the standby redo logs

  1. Enviroment.
  2. SET STANDBY_FILE_MANAGEMENT=’MANUAL’
  3. Drop SRL On Standby.
  4. SET STANDBY_FILE_MANAGEMENT=’AUTO’
  5. Enable MRP.
  6. Enviroment.
  7. SET STANDBY_FILE_MANAGEMENT=’MANUAL’
  8. Drop SRL On Standby.

How do I change Archivear to Noarchivelog?

To change the archiving mode from NOARCHIVELOG to ARCHIVELOG, follow the steps below:

  1. Invoke SQL*Plus and connect as a user with SYSDBA privileges.
  2. Shut down the database instance using the NORMAL, IMMEDIATE, or TRANSACTIONAL option: SHUTDOWN IMMEDIATE.

What is redo log corruption error?

Redo log corruption errors in one of the redo log files while the database is open. The redo log corruption could be any of these errors: ORA-16038 log %s sequence# %s cannot be archived ORA-354 corrupt redo log block header ORA-353 log corruption near block change time ORA-367 checksum error in log file header

Why is my redo log file not working?

The reason being your redo log file of that group is corrupted so you are losing your data anyways. Also if you want the group back you will have recreate the group and add a redo log member thus increasing your own efforts. So I guess it’s time to go back to the most dangerous DBA’s command and see what happens after we execute it.

Why can’t I run alter database clear logfile?

The reason is: If the status of your redo log file is CURRENT then there is no archive log file created of that particular redo log file. Hence we cannot run ALTER DATABASE CLEAR LOGFILE. 1 INACTIVE C:\\APP\\PC\\ORADATA\\ADMIN\\ REDO04.

How do I check the status of my redo log files?

Step 1: Check the status of your redo log files. 1 INACTIVE C:\\APP\\PC\\ORADATA\\ADMIN\\ REDO04. LOG 1 INACTIVE C:\\APP\\PC\\ORADATA\\ADMIN\\ REDO01. LOG 2 CURRENT C:\\APP\\PC\\ORADATA\\ADMIN\\ REDO02.

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