?

The VALID_FOR attribute is used to specify when redo transport servicestransmits redo data to a redo transport destination. Oracle recommends that theva lID_FOR attribute be specified for eachredo transport destination at every site in a Data Guard configuration so thatredo transport services will continue to send redo data to all standbydatabases after a role transition, regardless of which standby database assumesthe primary role.

The REOPEN attribute is used to specify the minimum numberof seconds between automatic reconnect attempts to a redo transport destinationthat is inactive because of a previous error.

?

The COMPRESSION attribute is used to specify that redo data is transmitted to aredo transport destination in compressed form. Redo transport compression cansignificantly improve redo transport performance on network links with lowbandwidth and high latency.

Redo transport compression is afeature of the Oracle Advanced Compression option. You must purchase a licensefor this option before using the redo transport compression feature.

?

The following example uses all of the LOG_ARCHIVE_DEST_n attributes described in thissection. A DB_UNIQUE_NAME has been specified for bothdestinations, as has the use of compression. If a redo transport fault occursat either destination, redo transport will attempt to reconnect to thatdestination, but not more frequently than once every 60 seconds.

?

?

?

DB_UNIQUE_NAME=BOSTON

LOG_ARCHIVE_CONFIG='DG_CONFIG=(BOSTON,CHICAGO,HARTFORD)'

LOG_ARCHIVE_DEST_2='SERVICE=CHICAGOASYNC NOAFFIRM VALID_FOR=(ONLINE_LOGFILE,

PRIMARY_ROLE)REOPEN=60 COMPRESSION=ENABLE DB_UNIQUE_NAME=CHICAGO'

LOG_ARCHIVE_DEST_STATE_2='ENABLE'

LOG_ARCHIVE_DEST_3='SERVICE=HARTFORDSYNC AFFIRM NET_TIMEOUT=30

VALID_FOR=(ONLINE_LOGFILE,PRIMARY_ROLE)REOPEN=60 COMPRESSION=ENABLE

DB_UNIQUE_NAME=HARTFORD'

LOG_ARCHIVE_DEST_STATE_3='ENABLE'

?