ORA-19555 invalid LOG_ARCHIVE_MIN_SUCCEED_DEST parameter value

Cause: The value of parameter LOG_ARCHIVE_MIN_SUCCEED_DEST was not set within the valid range.

Action:Specify a correct value for parameter LOG_ARCHIVE_MIN_SUCCEED_DEST.If the archive log parameters LOG_ARCHIVE_DEST or LOG_ARCHIVE_DUPLEX_DEST are in use, set parameter LOG_ARCHIVE_MIN_SUCCEED_DEST to either 1 or 2.

Read More

Setting Initial Database ArchiveLog Mode

You set the initial archiving mode as part of database creation in the CREATE DATABASE statement. Usually, you can use the default of NOARCHIVELOG mode at database creation because there is no need to archive the redo information generated by that process. After creating the database, decide whether to change the initial archiving mode. If you specify ARCHIVELOG mode, you must have initialization parameters set that specify the destinations for the archive log files

Changing the Database Archiving Mode

To change the archiving mode of the database, use the ALTER DATABASE statement with the ARCHIVELOG or NOARCHIVELOG clause. To change the archiving mode, you must be connected to the database with administrator privileges (AS SYSDBA).

The following steps switch the database archiving mode from NOARCHIVELOG to ARCHIVELOG:

1) Shut down the database instance

 SHUTDOWN

 An open database must first be closed and any associated instances shut down before you can switch   the database archiving mode. You cannot change the mode from ARCHIVELOG to NOARCHIVELOG if any datafiles need media recovery.

2) Back up the database.

Before making any major change to a database, always back up the database to protect against any problems. This will be your final backup of the database in NOARCHIVELOG mode and can be used if something goes wrong during the change to ARCHIVELOG mode

3) Edit the initialization parameter file to include the initialization parameters that specify the destinations for the archive log files

4) Start a new instance and mount, but do not open, the database.

STARTUP MOUNT

To enable or disable archiving, the database must be mounted but not open.

5) Change the database archiving mode. Then open the database for normal operations.

ALTER DATABASE ARCHIVELOG;

ALTER DATABASE OPEN;

6) Shut down the database.

SHUTDOWN IMMEDIATE

7) Back up the database.

Changing the database archiving mode updates the control file. After changing the database archiving mode, you must back up all of your database files and control file. Any previous backup is no longer usable because it was taken in NOARCHIVELOG mode.

Read More

ArchiveLog Mode

When you run a database in ARCHIVELOG mode, you enable the archiving of the redo log. The database control file indicates that a group of filled redo log files cannot be reused by LGWR until the group is archived. A filled group becomes available for archiving immediately after a redo log switch occurs.

The archiving of filled groups has these advantages:

•  A database backup, together with online and archived redo log files, guarantees that you can recover all committed transactions in the event of an operating system or disk failure. 
• If you keep an archived log, you can use a backup taken while the database is open and in normal system use.
• You can keep a standby database current with its original database by continuously applying the original archived redo logs to the standby.

You can configure an instance to archive filled redo log files automatically, or you can archive manually. For convenience and efficiency, automatic archiving is usually best. 

If all databases in a distributed database operate in ARCHIVELOG mode, you can perform coordinated distributed database recovery. However, if any database in a distributed database is in NOARCHIVELOG mode, recovery of a global distributed database (to make all databases consistent) is limited by the last full backup of any database operating in NOARCHIVELOG mode

Related Post :- Setting the Initial Database Archiving Mode

Read More

NoArchiveLog Mode and ArchiveLog Mode

You set the initial archiving mode as part of database creation in the CREATE DATABASE statement. Usually, you can use the default of NOARCHIVELOG mode at database creation because there is no need to archive the redo information generated by that process. After creating the database, decide whether to change the initial archiving mode.

If you specify ARCHIVELOG mode, you must have initialization parameters set that specify the destinations for the archive log files.

This section describes the issues you must consider when choosing to run your database in NOARCHIVELOG or ARCHIVELOG mode, and contains these topics:

• Running a Database in NOARCHIVELOG Mode
• Running a Database in ARCHIVELOG Mode

Read More

Archived Redo Logs Files

What Is the Archived Redo Log?

Oracle Database lets you save filled groups of redo log files to one or more offline destinations, known collectively as the archived redo log, or more simply the archive log. The process of turning redo log files into archived redo log files is called archiving. This process is only possible if the database is running in ARCHIVELOG mode. You can choose automatic or manual archiving.

An archived redo log file is a copy of one of the filled members of a redo log group. It includes the redo entries and the unique log sequence number of the identical member of the redo log group. For example, if you are multiplexing your redo log, and if group 1 contains identical member files a_log1 and b_log1, then the archiver process (ARCn) will archive one of these member files. Should a_log1 become corrupted, then ARCn can still archive the identical b_log1. The archived redo log contains a copy of every group created since you enabled archiving.

When the database is running in ARCHIVELOG mode, the log writer process (LGWR) cannot reuse and hence overwrite a redo log group until it has been archived. The background process ARCn automates archiving operations when automatic archiving is enabled. The database starts multiple archiver processes as needed to ensure that the archiving of filled redo logs does not fall behind.

You can use archived redo logs to:

Recover a database

Update a standby database

Get information about the history of a database using the LogMiner utility


Related Post: NOARCHIVELOG and ARCHIVELOG Mode

Read More