Data Guard Redo Log Reuse Tips Oracle Tips by Burleson Consulting December 9, 2011

Oracle Data Guard - Log Management Services

Online Redo Logs Reuse Policy

Setting the remote archiving destination to MANDATORY may have adverse effects on the primary database. If archiving to the mandatory destination fails or takes longer to complete, the primary database will suspend. This attribute setting should be evaluated in conjunction with the performance requirement of the database. This attribute can be set as shown below:

LOG_ARCHIVE_DEST_2 = ‘SERVICE=appsstdby1 MANDATORY’
LOG_ARCHIVE_DEST_3 = ‘SERVICE=appsstdby2 OPTONAL’

The default value is OPTIONAL for all types of archival destination. All 10 archive log destinations can be set as OPTIONAL, but it is recommended to keep at least one local archive destination as a MANDATORY location. Column BINDING of v$archive_dest view provides the information on this attribute.

Retrying Archiving to a Failed Destination

The log_archive_dest_n parameter has two attributes called REOPEN and MAX_FAILURE.  These attributes can be set so that the archiver on the primary database will try to re-transmit the archived redo logs to the archive destination if the previous attempt of archival failed. The value of MAX_FAILURE specifies the number of times the archiver will try to re-transmit the log file before marking the destination as NOREOPEN.  The value of REOPEN specifies the delay, in seconds, before the archiver makes another attempt to send log files. The REOPEN and MAX_FAILURE attributes can be specified as shown in the following example: