Data Guard Switchover Problem
During a recent test of our switchover process on our production environment, the SQL in the log files was not applied to the new logical
standby database. The archives logs are transferred to the logical standby, but the SQL is not applied. We had to perform a manual process to keep the
databases in sync. We also had problems with the switchback because of this problem. The manual workaround process is described below:
Run the following query--
set pagesize 1000
SELECT L.thread#, L.sequence#, L.first_time,
(CASE WHEN L.next_change#
WHEN L.first_change# < p.applied_scn THEN 'CURRENT'
ELSE 'NO' END) APPLIED
FROM DBA_LOGSTDBY_LOG L, DBA_LOGSTDBY_PROGRESS P
WHERE L.first_time > sysdate - 3
ORDER BY thread#, SEQUENCE#
THREAD# SEQUENCE# FIRST_TIME APPLIED
---------- ---------- -------------------- -------
1 62481 Jun-02-2007 18:20:22 NO
1 62482 Jun-02-2007 18:30:05 NO
1 62483 Jun-02-2007 18:30:09 NO
1 62484 Jun-02-2007 18:31:02 NO
1 62485 Jun-02-2007 18:51:04 NO
1 62486 Jun-02-2007 19:11:06 NO
2 61123 Jun-02-2007 18:20:15 NO
2 61124 Jun-02-2007 18:30:05 NO
2 61125 Jun-02-2007 18:30:09 NO
2 61126 Jun-02-2007 18:32:27 NO
2 61127 Jun-02-2007 18:33:27 NO
2 61128 Jun-02-2007 18:53:27 NO
2 61129 Jun-02-2007 19:13:28 NO
13 rows selected.
2. Delete archive log with the latest sequence number from cluster1. The example this would be --62486. The log is located in /u03/oracle/archive/
and is the latest log from the Primary database cluster 1.
3. The next step is to register the logfile using the following command alter database register
logical logfile '/u03/oracle/archive/standby/log_instance_1_
4. The process changes the no's to current or yes. The process has to be repeated as
the logs are transferred to the new standby to keep the databases in sync.
Some of the errors that we saw during the switchover are listed below:
The following error started after completion of the alter database commit to switchover to
logical primary command completed successfully:
Error Group 1
ORA-02068: following severe error from instance2
ORA-03113: end-of-file on communication channel
The Instance1 database was generating an error talking to Instance2. There is a database link
configured for communication between Instance1 and and Instance2 (RAC)
Both databases have a matching standby database. Instance1_STB and Instance2_STB (non-RAC)
Errors Group 2 ( on instance 1 & 2)
ORA-00321: log 1 of thread 1, cannot update log file header
ORA-00312: online log 1 thread 1: '/u01/oracle/oradata/instance2/log1_01a.rdo'
ORA-17500: ODM err:ODM ERROR V-41-4-1-83-9 Bad file number
Has anyone had this type of problem where after you switchover you cannot get the new standby to automatically apply logs.