oracle some of the parameters

Aug 11 posted in Oracle (RSS), 135 views.

1, AFFIRM and NOAFFIRM
Role: Control the log transport service is asynchronous or synchronous write log data to disk
AFFIRM: in the log before the writing process, so the archive logs and database logs must be synchronized finish prepare
NOFFIRM: in the main library to write log of all disk IO to complete the process varies

The default is the NOFFIRM
The use of AFFIRM, you can ensure that the following three points:
1 can ensure that data is not lost after the failure of the main library
2 can be used locally or remotely using
3 affect the performance of the main library
LGWR and AFFIRM, the log writing process synchronization write REDO DATA to disk, in the DISK finish before the control is not handed over to the user, as well as the main library's online logs may not be available before the completion of the archive

ARCH and AFFIRM ARCn process synchronization write REDO DATA to disk, archiving operation may occur rather a long time, the main library's online journal in the archive may not be available before the completion of the log.
ASYNC and AFFIRM, the performance is not affected.

2, ALTERNATE
Effect: When the original archive destination fails, you can use after the meeting of the, but if REOPEN parameter is not O, then, ALTERNATE will not be available.
MAX FAILURE if the value is not 0, when the implementation of the specified number of retries after a failure, ALTERNATE will prepare the opening, therefore, ALTERNATE will not, and REPOPEN conflict (REOPEN not 0)

Instructions for use:
ALTERNATE is optional, if not set, the log transport services will not automatically switch archive path is not available if the original path that you can specify an ALTERNATE for each one LOG_ARCHIVE_DEST, but can share the same one ALTERNATE
LOG_ARCHIVE_DEST_1 = 'LOCATION = / disk1 MANDATORY ALTERNATE = LOG_ARCHIVE_DEST_2'
LOG_ARCHIVE_DEST_STATE_1 = ENABLE
LOG_ARCHIVE_DEST_2 = 'LOCATION = / disk2 MANDATORY'
LOG_ARCHIVE_DEST_STATE_2 = ALTERNATE
LOG_ARCHIVE_DEST_1 = 'LOCATION = / disk1 MANDATORY'
LOG_ARCHIVE_DEST_STATE_1 = ENABLE
LOG_ARCHIVE_DEST_2 = 'SERVICE = stby1_path1 OPTIONAL ALTERNATE = LOG_ARCHIVE_DEST_3'
LOG_ARCHIVE_DEST_STATE_2 = ENABLE
LOG_ARCHIVE_DEST_3 = 'SERVICE = stby1_path2 OPTIONAL'
LOG_ARCHIVE_DEST_STATE_3 = ALTERNATE
3 ARCH and LGWR

Role: The log transport service using the ARCH or LGWR,
The default is ARCH
Note that if you change the current archiving process, such as from ARCn to LGWR, only the log switch has. Changes to take effect.
LOG_ARCHIVE_DEST_3 = 'SERVICE = denver LGWR'
LOG_ARCHIVE_DEST_STATE_3 = ENABLE

4 DB_UNIQUE_NAME

The path marked only if you use the second parameter is usually set LOG_ARCHIVE_CONFIG = DG_CONFIG () the two should match, as well as parameter files must be consistent use of this parameter is mainly to clear the main library and the library to use that path to prepare

DB_UNIQUE_NAME = boston
LOG_ARCHIVE_CONFIG = 'DG_CONFIG = (chicago, boston, denver)'
LOG_ARCHIVE_DEST_1 = 'LOCATION = / arch1 /
VALID_FOR = (ALL_LOGFILES, ALL_ROLES)
DB_UNIQUE_NAME = boston '
LOG_ARCHIVE_DEST_2 = 'SERVICE = Sales_DR
VALID_FOR = (ONLINE_LOGFILES, PRIMARY_ROLE)
DB_UNIQUE_NAME = chicago '

5, DELAY
Role:
Provides: REDO data in the database archiving and application prepared by the time the default is no delay
The DELAY attribute is optional. By default there is no delay.

The DELAY attribute indicates the archived redo log files at the standby destination are
not available for recovery until the specified time interval has expired.
The time interval is expressed in minutes, and it starts
when the redo data is successfully transmitted to, and archived at, the standby site.

The DELAY attribute may be used to protect a standby database from corrupted or
erroneous primary data. However, there is a tradeoff because during failover
it takes more time to apply all of the redo up to the point of corruption.

The DELAY attribute does not affect the transmittal of redo data to a standby destination.

If you have real-time apply enabled, any delay that you set will be ignored.

Changes to the DELAY attribute take effect the next time redo data is archived (after a log switch).
In-progress archiving is not affected.

You can override the specified delay interval at the standby site, as follows:

For a physical standby database:

SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE NODELAY;

For a logical standby database:

SQL> ALTER DATABASE START LOGICAL STANDBY APPLY NODELAY;

Example:
LOG_ARCHIVE_DEST_1 = 'LOCATION = / oracle / dbs /'
LOG_ARCHIVE_DEST_STATE_1 = ENABLE
LOG_ARCHIVE_DEST_2 = 'SERVICE = stbyB LGWR SYNC AFFIRM'
LOG_ARCHIVE_DEST_STATE_2 = ENABLE
LOG_ARCHIVE_DEST_3 = 'SERVICE = stbyC DELAY = 120'
LOG_ARCHIVE_DEST_STATE_3 = ENABLE

6, location and service
Each path must be local or through a service named

Example 1 Specifying the LOCATION Attribute

LOG_ARCHIVE_DEST_2 = 'LOCATION = / disk1/oracle/oradata/payroll/arch /'
LOG_ARCHIVE_DEST_STATE_2 = ENABLE
Example 2 Specifying the SERVICE Attribute

LOG_ARCHIVE_DEST_3 = 'SERVICE = stby1'
LOG_ARCHIVE_DEST_STATE_3 = ENABLE

7, MANDATORY and OPTIONAL

MANDATORY: online log reused, it must prepare a successful archive
OPTIONAL: In-line logs can be re-prepared before the filing does not require success DESTINATION default for the OPTIONAL
You must have at least one local destination, which you can declare OPTIONAL or MANDATORY.

At least one local destination is operationally treated as mandatory, because the minimum value for the LOG_ARCHIVE_MIN_SUCCEED_DEST parameter is 1.

The failure of any mandatory destination, including a mandatory standby destination, makes the LOG_ARCHIVE_MIN_SUCCEED_DEST parameter irrelevant.

The LOG_ARCHIVE_MIN_SUCCEED_DEST parameter value cannot be greater than the number of mandatory destinations plus the number of optional local destinations.

These attributes do not affect the data protection mode for the destination.

The BINDING column of the V $ ARCHIVE_DEST fixed view specifies how failure affects the archival operation

Examples

The following example shows the MANDATORY attribute:

LOG_ARCHIVE_DEST_1 = 'LOCATION = / arch / dest MANDATORY'
LOG_ARCHIVE_DEST_STATE_1 = ENABLE
LOG_ARCHIVE_DEST_3 = 'SERVICE = denver MANDATORY'
LOG_ARCHIVE_DEST_STATE_3 = ENABLE