Tuesday, January 22, 2008

LOG_ARCHIVE_DEST_n

Syntax LOG_ARCHIVE_DEST_[1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10] =

"null_string" |

((SERVICE=service

| LOCATION=location)

[AFFIRM | NOAFFIRM]

[ALTERNATE=destination | NOALTERNATE]

[ARCH | LGWR]

[DELAY[=minutes] | NODELAY]

[DEPENDENCY=destination | NODEPENDENCY]

[MANDATORY | OPTIONAL]

[MAX_FAILURE=count | NOMAX_FAILURE]

[QUOTA_SIZE=blocks | NOQUOTA_SIZE]

[QUOTA_USED=blocks | NOQUOTA_USED]

[REGISTER | NOREGISTER]

[REGISTER=location_format]

[REOPEN[=seconds] | NOREOPEN]

[SYNC | ASYNC=blocks]] )

Default value There is no default value.

Parameter class Dynamic: ALTER SESSION, ALTER SYSTEM

Range of values Valid keyword definitions

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Note:
This parameter is valid only if you have installed Oracle Enterprise Edition. You may continue to use LOG_ARCHIVE_DEST if you have installed Oracle Enterprise Edition. However, you cannot use both LOG_ARCHIVE_DEST_n and LOG_ARCHIVE_DEST, as they are not compatible.

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The LOG_ARCHIVE_DEST_n parameters (where n = 1, 2, 3, ... 10) define up to ten archive log destinations. The parameter integer suffix is defined as the handle displayed by the V$ARCHIVE_DEST dynamic performance view.

Values:

SERVICE

Specifies a standby destination. Oracle Net (IPC or TCP) transmits the archivelog. A standby instance must be associated with the destination. The value represented by tnsnames_service corresponds to an appropriate service name in tnsnames.ora.

LOCATION

Specifies a local file system destination. You must specify this parameter for at least one destination.

MANDATORY

Specifies that archiving to the destination must succeed before the redo log file can be made available for reuse.

OPTIONAL

Specifies that successful archiving to the destination is not required before the redo log file can be made available for reuse. If the "must succeed count," set with LOG_ARCHIVE_MIN_SUCCEED_DEST, is met, the redo logfile is marked for reuse. This is the default.

REOPEN

Specifies an interval of time (in seconds) that must pass after an error has been encountered during archiving to the destination before future archives to the destination can be attempted. Future attempts are made when the next redo log file is archived. If a destination is MANDATORY, Oracle Corporation recommends that you specify a REOPEN time that reduces the possibility of primary database shutdown due to lack of available online redo log files.

If you do not specify integer, the default value is 300 seconds. If you do not specify REOPEN, the archiver process will never reopen a destination after an error.


Examples:
LOG_ARCHIVE_DEST_1 = 'LOCATION=/u01/oracle/logs MANDATORY REOPEN=120'
LOG_ARCHIVE_DEST_2 = 'SERVICE=standby1 MANDATORY REOPEN=180'
LOG_ARCHIVE_DEST_3 = 'SERVICE=standby2 OPTIONAL'

Note:
- This parameter is only valid for Oracle Enterprise Edition.
- This parameter introduced in Oracle 8i.
- You may continue to use LOG_ARCHIVE_DEST if you have installed Oracle
Enterprise Edition. However, you cannot use both LOG_ARCHIVE_DEST_n and
LOG_ARCHIVE_DEST, as they are not compatible.

7 comments:

  1. It's important for database performance and recovery that log archive destinations are properly configured.

    ReplyDelete