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Oracle® Data Guard Concepts and Administration
11g Release 2 (11.2)

Part Number E10700-01
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15 LOG_ARCHIVE_DEST_n Parameter Attributes

This chapter provides reference information for the attributes of the LOG_ARCHIVE_DEST_n initialization parameter, where n is an integer between 1 and 31. The following list shows the attributes for the parameter:

Usage Notes

Note:

Several attributes of the LOG_ARCHIVE_DEST_n initialization parameter have been deprecated. These attributes are supported for backward compatibility only and are documented in the Oracle Database Reference.

See Also:

Chapter 6 for more information about defining LOG_ARCHIVE_DEST_n destinations and setting up redo transport services

AFFIRM and NOAFFIRM

Controls whether a redo transport destination acknowledges received redo data before or after writing it to the standby redo log:

Category AFFIRM NOAFFIRM
Data type Keyword Keyword
Valid values Not applicable Not applicable
Default Value Not applicable Not applicable
Requires attributes SERVICE SERVICE
Conflicts with attributes NOAFFIRM AFFIRM
Corresponds to AFFIRM column of the V$ARCHIVE_DEST view AFFIRM column of the V$ARCHIVE_DEST view

Usage Notes

See also:

SYNC and ASYNC attributes

Examples

The following example shows the AFFIRM attribute for a remote destination.

LOG_ARCHIVE_DEST_3='SERVICE=stby1 SYNC AFFIRM'
LOG_ARCHIVE_DEST_STATE_3=ENABLE

ALTERNATE

Specifies an alternate archiving destination to be used when the original destination fails.

Category ALTERNATE=LOG_ARCHIVE_DEST_n
Data Type String
Valid Value A LOG_ARCHIVE_DEST_n destination, where n is a value from 1 through 10.
Default Value None. If an alternate destination is not specified, then redo transport services do not automatically change to another destination.
Requires attributes Not applicable
Conflicts with attributes None Foot 1 
Corresponds to ALTERNATE and STATUS columns of the V$ARCHIVE_DEST view

Footnote 1 If the REOPEN attribute is specified with a nonzero value, the ALTERNATE attribute is ignored. If the MAX_FAILURE attribute is also specified with a nonzero value, and the failure count exceeds the specified failure threshold, the ALTERNATE destination is enabled. Therefore, the ALTERNATE attribute does not conflict with a nonzero REOPEN attribute value.

Usage Notes

Examples

In the sample initialization parameter file in Example 15-1, LOG_ARCHIVE_DEST_1 automatically fails over to LOG_ARCHIVE_DEST_2 on the next archival operation if an error occurs or the device becomes full.

Example 15-1 Automatically Failing Over to an Alternate Destination

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

Notice in the example that a destination can also be in the ALTERNATE state, as specified with the LOG_ARCHIVE_DEST_STATE_n initialization parameter. The ALTERNATE state defers redo transport services from transmitting redo data to this destination until such time as another destination failure automatically enables this destination.

Example 15-2 Defining an Alternate Oracle Net Service Name to the Same Standby Database

This example shows how to define an alternate Oracle Net service name to the same standby database.

LOG_ARCHIVE_DEST_1='LOCATION=/disk1 MANDATORY'
LOG_ARCHIVE_DEST_STATE_1=ENABLE
LOG_ARCHIVE_DEST_2='SERVICE=stby1_path1 ALTERNATE=LOG_ARCHIVE_DEST_3'
LOG_ARCHIVE_DEST_STATE_2=ENABLE
LOG_ARCHIVE_DEST_3='SERVICE=stby1_path2'
LOG_ARCHIVE_DEST_STATE_3=ALTERNATE

COMPRESSION

The COMPRESSION attribute is used to specify whether redo data is compressed before transmission to a redo transport destination.

Note:

Redo transport compression is a feature of the Oracle Advanced Compression option. You must purchase a license for this option before using the redo transport compression feature.
Category COMPRESSION=ENABLE or DISABLE
Data Type Boolean
Valid values ENABLE or DISABLE
Default value DISABLE
Requires attributes None
Conflicts with attributes None
Corresponds to COMPRESSION column of the V$ARCHIVE_DEST view

Usage Notes

Example

The following example shows the COMPRESSION attribute with the LOG_ARCHIVE_DEST_n parameter.

LOG_ARCHIVE_DEST_3='SERVICE=denver SYNC COMPRESSION=ENABLE'
LOG_ARCHIVE_DEST_STATE_3=ENABLE

DB_UNIQUE_NAME

Specifies a unique name for the database at this destination.

Category DB_UNIQUE_NAME=name
Data Type String
Valid values The name must match the value that was defined for this database with the DB_UNIQUE_NAME parameter.
Default value None
Requires attributes None
Conflicts with attributes None
Corresponds to DB_UNIQUE_NAME column of the V$ARCHIVE_DEST view

Usage Notes

Example

In the following example, the DB_UNIQUE_NAME parameter specifies boston (DB_UNIQUE_NAME=boston), which is also specified with the DB_UNIQUE_NAME attribute on the LOG_ARCHIVE_DEST_1 parameter. The DB_UNIQUE_NAME attribute on the LOG_ARCHIVE_DEST_2 parameter specifies the chicago destination. Both boston and chicago are listed in the LOG_ARCHIVE_CONFIG=DG_CONFIG parameter.

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'

DELAY

Specifies a time lag between when redo data is archived on a standby site and when the archived redo log file is applied to the standby database.

Category DELAY[=minutes]
Data Type Numeric
Valid values >=0 minutes
Default Value 30 minutes
Requires attributes SERVICE
Conflicts with attributes LOCATION
Corresponds to DELAY_MINS and DESTINATION columns of the V$ARCHIVE_DEST view

Usage Notes

See Also:

Oracle Database SQL Language Reference for more information about these ALTER DATABASE statements

Examples

You can use the DELAY attribute to set up a configuration where multiple standby databases are maintained in varying degrees of synchronization with the primary database. However, this protection incurs some overhead during failover, because it takes Redo Apply more time to apply all the redo up to the corruption point.

For example, assume primary database A has standby databases B and C. Standby database B is set up as the disaster recovery database and therefore has no time lag. Standby database C is set up with a 2-hour delay, which is enough time to allow user errors to be discovered before they are propagated to the standby database.

The following example shows how to specify the DELAY attribute for this configuration:

LOG_ARCHIVE_DEST_1='LOCATION=/arch/dest MANDATORY'
LOG_ARCHIVE_DEST_STATE_1=ENABLE
LOG_ARCHIVE_DEST_2='SERVICE=stbyB SYNC AFFIRM'
LOG_ARCHIVE_DEST_STATE_2=ENABLE
LOG_ARCHIVE_DEST_3='SERVICE=stbyC DELAY=120'
LOG_ARCHIVE_DEST_STATE_3=ENABLE

Note:

Alternatively, you can use Flashback Database to revert the database to a point-in-time or SCN in a different database incarnation as long as there is sufficient flashback log data. Using Flashback Database is described in Oracle Database Backup and Recovery User's Guide.

LOCATION and SERVICE

Each destination must specify either the LOCATION or the SERVICE attribute to identify either a local disk directory or a remote database destination where redo transport services can transmit redo data.

LOG_ARCHIVE_DEST_1 through LOG_ARCHIVE_DEST_10 destinations can contain either a LOCATION attribute or a SERVICE attribute.

LOG_ARCHIVE_DEST_11 through LOG_ARCHIVE_DEST_31 destinations can only contain a SERVICE attribute.

Category LOCATION=local_disk_directory or USE_DB_RECOVERY_FILE_DEST SERVICE=net_service_name
Data type String value String value
Valid values Not applicable Not applicable
Default Value None None
Requires attributes Not applicable Not applicable
Conflicts with attributes SERVICE, DELAY, NOREGISTER, SYNC, ASYNC, NET_TIMEOUT, AFFIRM,NOAFFIRM, COMPRESSION, MAX_CONNECTIONS LOCATION
Corresponds to DESTINATION and TARGET columns of the V$ARCHIVE_DEST view DESTINATION and TARGET columns of the V$ARCHIVE_DEST view

Usage Notes

Examples

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

MANDATORY

Specifies that filled online log files must be successfully archived to the destination before they can be reused.

Category MANDATORY
Data type Keyword
Valid values Not applicable
Default value Not applicable
Requires attributes Not applicable
Conflicts with attributes Optional
Corresponds to BINDING column of the V$ARCHIVE_DEST view

Usage Notes

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

MAX_CONNECTIONS

Enables multiple network connections to be used when sending an archived redo log file to a redo transport destination. Using multiple network connections can improve redo transport performance over high-latency network links.

Category Description
Data type Integer
Valid values 1 to 5
Default value 1
Requires attributes None
Conflicts with attributes None
Corresponds to MAX_CONNECTIONS column of the V$ARCHIVE_DEST view of the primary database

Usage Notes

Examples

The following example shows the MAX_CONNECTIONS attribute:

LOG_ARCHIVE_DEST_1='LOCATION=/arch/dest'
LOG_ARCHIVE_DEST_STATE_1=ENABLE
LOG_ARCHIVE_DEST_3='SERVICE=denver MAX_CONNECTIONS=3'
LOG_ARCHIVE_DEST_STATE_3=ENABLE

MAX_FAILURE

Controls the consecutive number of times redo transport services attempt to reestablish communication and transmit redo data to a failed destination before the primary database gives up on the destination.

Category MAX_FAILURE=count
Data type Numeric
Valid value >=0
Default value None
Requires attributes REOPEN
Conflicts with attributes None
Corresponds to MAX_FAILURE, FAILURE_COUNT, and REOPEN_SECS columns of the V$ARCHIVE_DEST view

Usage Notes

Examples

The following example allows redo transport services up to three consecutive archival attempts, tried every 5 seconds, to the arc_dest destination. If the archival operation fails after the third attempt, the destination is treated as if the REOPEN attribute was not specified.

LOG_ARCHIVE_DEST_1='LOCATION=/arc_dest REOPEN=5 MAX_FAILURE=3'
LOG_ARCHIVE_DEST_STATE_1=ENABLE

NET_TIMEOUT

Specifies the number of seconds that the LGWR background process will block waiting for a redo transport destination to acknowledge redo data sent to it. If an acknowledgement is not received within NET_TIMEOUT seconds, an error is logged and the redo transport session to that destination is terminated.

Category NET_TIMEOUT=seconds
Data type Numeric
Valid values 1Foot 1  to 1200
Default value 30 seconds
Requires attributes SYNC
Conflicts with attributes ASYNC (If you specify the ASYNC attribute, redo transport services ignores it; no error is returned.)
Corresponds to NET_TIMEOUT column of the V$ARCHIVE_DEST view of the primary database

Footnote 1 Although a minimum value of 1 second is allowed, Oracle recommends a minimum value of 8 to 10 seconds to avoid disconnecting from the standby database due to transient network errors.

Usage Notes

Examples

The following example shows how to specify a 10-second network timeout value on the primary database with the NET_TIMEOUT attribute.

LOG_ARCHIVE_DEST_2='SERVICE=stby1 SYNC NET_TIMEOUT=10'
LOG_ARCHIVE_DEST_STATE_2=ENABLE

NOREGISTER

Indicates that the location of the archived redo log file should not be recorded at the corresponding destination.

Category NOREGISTER
Data type Keyword
Valid values Not applicable
Default value Not applicable
Requires attributes SERVICE
Conflicts with attributes LOCATION
Corresponds to DESTINATION and TARGET columns of the V$ARCHIVE_DEST view

Usage Notes

Examples

The following example shows the NOREGISTER attribute:

LOG_ARCHIVE_DEST_5='NOREGISTER'

REOPEN

Specifies the minimum number of seconds before redo transport services should try to reopen a failed destination.

Category REOPEN [=seconds]
Data Type Numeric
Valid values >=0 seconds
Default Value 300 seconds
Requires attributes None
Conflicts with attributes Not applicable
Corresponds to REOPEN_SECS and MAX_FAILURE columns of the V$ARCHIVE_DEST view

Usage Notes

Examples

The following example shows the REOPEN attribute.

LOG_ARCHIVE_DEST_3='SERVICE=stby1 MANDATORY REOPEN=60'
LOG_ARCHIVE_DEST_STATE_3=ENABLE

SYNC and ASYNC

Specifies whether the synchronous (SYNC) or asynchronous (ASYNC) redo transport mode is to be used.

Category SYNC ASYNC
Data type Keyword Keyword
Valid values Not applicable Not applicable
Default value Not applicable None
Requires attributes None None
Conflicts with attributes ASYNC, LOCATION SYNC, LOCATION
Corresponds to TRANSMIT_MODE column of the V$ARCHIVE_DEST view TRANSMIT_MODE and column of the V$ARCHIVE_DEST view

Usage Notes

Examples

The following example shows the SYNC attribute with the LOG_ARCHIVE_DEST_n parameter.

LOG_ARCHIVE_DEST_3='SERVICE=stby1 SYNC'
LOG_ARCHIVE_DEST_STATE_3=ENABLE

TEMPLATE

Defines a directory specification and format template for names of archived redo log files at the destination. The template is used to generate a filename that is different from the default filename format defined by the LOG_ARCHIVE_FORMAT initialization parameter at the redo destination.

Category TEMPLATE=filename_template_%t_%s_%r
Data Type String value
Valid values Not applicable
Default value None
Requires attributes ... SERVICE
Conflicts with attributes ... LOCATION
Corresponds to ... REMOTE_TEMPLATE and REGISTER columns of the V$ARCHIVE_DEST view

Usage Notes


VALID_FOR

Specifies whether redo data will be written to a destination, based on the following factors:

Category VALID_FOR=(redo_log_type, database_role)
Data Type String value
Valid values Not applicable
Default Value VALID_FOR=(ALL_LOGFILES, ALL_ROLES)
Requires attributes None
Conflicts with attributes None
Corresponds to VALID_NOW, VALID_TYPE, and VALID_ROLE columns in the V$ARCHIVE_DEST view

Usage Notes

Example

The following example shows the default VALID_FOR keyword pair:

LOG_ARCHIVE_DEST_1='LOCATION=/disk1/oracle/oradata VALID_FOR=(ALL_LOGFILES, ALL_ROLES)'

When this database is running in either the primary or standby role, destination 1 archives all log files to the /disk1/oracle/oradata local directory location.