LOG_ARCHIVE_DEST_n

Property	Description
Parameter type	String
Syntax	LOG_ARCHIVE_DEST_[1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10] = { null_string | { LOCATION=path_name | SERVICE=service_name } [ MANDATORY ] [ REOPEN[=seconds] ] [ DELAY[=minutes] ] [ NOREGISTER ] [ TEMPLATE=template ] [ ALTERNATE=destination ] [ DEPENDENCY=destination ] [ MAX_FAILURE=count ] [ SYNC | ASYNC ] [ AFFIRM | NOAFFIRM ] [ NET_TIMEOUT=seconds ] [ VALID_FOR=(redo_log_type,database_role) ] [ DB_UNIQUE_NAME ] [ MAX_CONNECTIONS=count ] [ COMPRESSION={ENABLE|DISABLE} ] }
Default value	There is no default value.
Modifiable	Most attributes are modifiable by ALTER SESSION and ALTER SYSTEM, but some are not. See Oracle Data Guard Concepts and Administration for further information.
Basic	Yes

The LOG_ARCHIVE_DEST_n initialization parameter defines up to 10 (where n = 1, 2, 3, ... 10) destinations, each of which must specify either the LOCATION or the SERVICE attribute to specify where to archive the redo data. All other attributes are optional. Note that whether you are specifying the LOCATION attribute or the SERVICE attribute, it must be the first attribute supplied in the list of attributes.

If you choose not to enter any attributes, then you can specify a NULL string by entering the following:

LOG_ARCHIVE_DEST_n=' ';

You set the attributes for the LOG_ARCHIVE_DEST_n initialization parameter to control different aspects of how redo transport services transfer redo data from a production or primary database destination to another (standby) database destination. You can query the V$ARCHIVE_DEST view to see the current attribute settings for each destination (n).

Note:

1. Some of the attributes for this parameter are deprecated, but are being retained for backward compatibility.

For every LOG_ARCHIVE_DEST_n initialization parameter that you define, you must specify a corresponding LOG_ARCHIVE_DEST_STATE_n parameter. The LOG_ARCHIVE_DEST_STATE_n (where n is an integer from 1 to 10) initialization parameter specifies whether the corresponding destination is currently enabled or disabled.

Values:

· AFFIRM and NOAFFIRM

Control whether or not redo transport services use synchronous or asynchronous disk I/O to write redo data to the archived redo log files. The default is NOAFFIRM.

· ALTERNATE=LOG_ARCHIVE_DEST_n

Specifies an alternate archiving destination to be used when the original destination fails. There is no default value; if an alternate destination is not specified, then archiving does not automatically change to another destination if the original destination fails.

· ASYNC

The redo data generated by a transaction need not have been received at a destination which has this attribute before that transaction can commit. This is the default behavior if neither SYNC nor ASYNC is specified.

· COMPRESSION

Indicates whether network compression is enabled or disabled.

· DB_UNIQUE_NAME=name

Specifies a unique name for the database at this destination. You must specify a name; there is no default value.

· DELAY[=minutes]

Specifies a time lag between when redo data is archived on a physical standby site and when the archived redo log file is applied to the physical standby database. You cannot set the DELAY attribute for a logical standby database destination. If you specify the DELAY attribute without a time interval, the default is 30 minutes.

· DEPENDENCY=LOG_ARCHIVE_DEST_n

Defines one archival destination to receive redo data on behalf of several destinations. Redo transport services transmit redo data to the destination that then shares its archived redo log files with multiple standby databases.

· LOCATION=local_disk_directory or USE_DB_RECOVERY_FILE_DEST

Specifies either a local file system destination or the directory, file system, or Automatic Storage Manager disk group that will serve as the flash recovery area. You must specify this attribute for at least one destination. You can specify either a local disk directory or flash recovery area with the LOCATION attribute. You must include either the LOCATION or the SERVICE attribute for each destination to specify where to archive the redo data.

· MANDATORY

Specifies that the transmission of redo data to the destination must succeed before the local online redo log file can be made available for reuse. If the MANDATORY attribute is not specified, then the destination is optional.

· MAX_CONNECTIONS

Specifies the maximum number of network connections that can be used to transmit redo data to this destination. The default is 1.

· 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 permanently gives up on the standby database.

· NET_TIMEOUT=seconds

Specifies the number of seconds the log writer process on the primary system waits for status from the network server (LNSn) process before terminating the network connection. The default is 30 seconds.

· NOREGISTER

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

· REOPEN[=seconds]

Specifies the minimum number of seconds before the archiver processes (ARCn) or the log writer process (LGWR) should try again to access a previously failed destination. The default is 300 seconds.

· SERVICE=net_service_name

Specifies a valid Oracle Net service name (SERVICE=net_service_name) that identifies the remote Oracle database instance to which redo data will be sent. Each destination must specify either the LOCATION or the SERVICE attribute. There is no default net service name.

· SYNC

The redo data generated by a transaction must have been received by every enabled destination which has this attribute before that transaction can commit.

· TEMPLATE=filename_template_%t_%s_%r

Specifies a pathname and a filename template for archived redo log files created at a redo transport destination that contain redo data from the database where this attribute is specified. This attribute overrides the value of the LOG_ARCHIVE_FORMAT initialization parameter at a redo transport destination. This attribute does not have a default value.

· VALID_FOR=(redo_log_type, database_role)

Identifies when redo transport services can transmit redo data to destinations based on the following factors:

o redo_log_type—whether online redo log files, standby redo log files, or both are currently being archived on the database at this destination

o database_role—whether the database is currently running in the primary or the standby role

Deprecated Attributes for LOG_ARCHIVE_DEST_n

The following attributes are deprecated for the LOG_ARCHIVE_DEST_n parameter. They are retained for backward compatibility only.

Deprecated Attribute	Alternative
ARCH	Specify SYNC or ASYNC. ASYNC is the default if neither attribute is specified.
LGWR	Specify SYNC or ASYNC. ASYNC is the default if neither attribute is specified.
OPTIONAL	Destinations are optional by default.
VERIFY	None. This attribute is only used with the deprecated ARCH attribute.

In addition, note the following changes to the ASYNC and SYNC attributes:

· The BLOCKS keyword on the ASYNC attribute is no longer needed.

It is no longer necessary to set this keyword because Data Guard dynamically adjusts the block count up or down to an appropriate number of blocks, as necessary.

· The PARALLEL and NOPARALLEL keywords on the SYNC attribute are no longer needed.

2. Related:    

   Parameter: LOG_ARCHIVE_DEST

   Parameter: LOG_ARCHIVE_DUPLEX_DEST

   Parameter: LOG_ARCHIVE_MIN_SUCCEED_DEST

 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'

  - 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. 

3. Query for the current value of the parameter

select name, value, isdefault, isses_modifiable, issys_modifiable,

isinstance_modifiable, isdeprecated, description

from v$parameter

where upper(name) like 'LOG_ARCHIVE_DEST_%';

NAME	VALUE	IS DEFAULT	ISSES_ MODIFIABLE	ISSYS_ MODIFIABLE	ISINSTANCE_ MODIFIABLE	IS DEPRECATED	DESCRIPTION
log_archive_dest_1	location=/mydb/archivelogs	FALSE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #1 text string
log_archive_dest_2		TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #2 text string
log_archive_dest_3		TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #3 text string
log_archive_dest_4		TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #4 text string
log_archive_dest_5		TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #5 text string
log_archive_dest_6		TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #6 text string
log_archive_dest_7		TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #7 text string
log_archive_dest_8		TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #8 text string
log_archive_dest_9		TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #9 text string
log_archive_dest_10		TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #10 text string
log_archive_dest_state_1	enable	TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #1 state text string
log_archive_dest_state_2	enable	TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #2 state text string
log_archive_dest_state_3	enable	TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #3 state text string
log_archive_dest_state_4	enable	TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #4 state text string
log_archive_dest_state_5	enable	TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #5 state text string
log_archive_dest_state_6	enable	TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #6 state text string
log_archive_dest_state_7	enable	TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #7 state text string
log_archive_dest_state_8	enable	TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #8 state text string
log_archive_dest_state_9	enable	TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #9 state text string
log_archive_dest_state_10	enable	TRUE	TRUE	IMMEDIATE	TRUE	FALSE	archival destination #10 state text string

Oracle initializatoin parameters