I have uploaded the material of the german presentation on Oracle Data Guard 11gr2 Whats New to the “presentation” section. It also contains 6 recorded demos using Enterprise Manager Grid Control.

I ran into this problem a couple of years ago but I still think that it is worth blogging about. Back then, I tried to setup a data guard broker enviroment but when trying to enable the configuration on the dgmgrl command line, the dataguard configuration files could not be synced to the standby host. After a couple of days of troubleshooting, it turned out that the Cisco ASA Firewall hat the SQL*Net Inspection Feature enabled. But because the data guard broker data packets did not exactly conform to SQL*Net, the Firewall corrupted the packet and it was not able to create the data guard configuration. After disabling the SQL*Net inspection, it worked without any further problems.

From time to time I have encountered the following errors on the physical dataguard standby database while in recovery mode:

Errors in file /oracle/STBDB1/oratrace/bdump/stbdb1_mrp0_26719.trc:
ORA-00322: log 5 of thread 1 is not current copy
ORA-00312: online log 5 thread 1: '/oracle/STBDB1/origlogB/standby_g5_m1.log'
Sun Oct 16 13:04:08 2008
Errors in file /oracle/STBDB1/oratrace/bdump/stbdb1_mrp0_26719.trc:
ORA-00322: log 5 of thread 1 is not current copy
ORA-00312: online log 5 thread 1: '/oracle/STBDB1/origlogB/standby_g5_m1.log'

The problem corrects itself after a couple of minutes, so there is no real problem, but if you have alert log monitoring active, this will trigger a call for investigation. Oracle is tracking this error with Bug 5238386 – ORA-322 possible reading standby redo log header. There is a one-off patch available for 10.2.0.3 and the patch is included in patchset 10.2.0.4.

There is a workaround to clear the referenced redo log but I don´t see any point in doing that, because the error can occurr again as long as the patch is not installed.