v$archive_dest Tips Oracle Database Tips by Donald BurlesonDecember 9, 2015

Oracle Data GuardChapter 5 - Log Management Services

Acknowledging Redo Disk I/O Operation on the Standby Database

When AFFIRM is used with LGWR, the log writer will wait for the disk I/O to complete on the standby site before the control is returned to application. Similarly, when it is used with ARCH, the archiver will not release online redo logs for LGWR to reuse until the redo log is completely and successfully archived on the standby site. The default setting is NOAFFIRM.

The following example shows a sample setting:

LOG_ARCHIVE_DEST_3='SERVICE=appsstdby1 LGWR AFFIRM'

The script, log_dest_attr.sql, from code depot to see the attributes of the log transfer service in the operating environment. A sample output of this script is shown below:

column dest_name     format a20 trunc
column binding       format a9
column reopen_secs   format 999
column alternate     format a20 trunc
column dependency    format a20 trunc
column transmit_mode format a12
column async_blocks  format 99999
column affirm        format a3

select
   dest_name,
   binding,
   reopen_secs,
   alternate,
   dependency,
   transmit_mode,
   decode(transmit_mode,'asynchronous',async_blocks,0)
          async_blocks,
   affirm
from
   See code depot for full scripts
   v$archive_dest;