ORA-16571 ORA-16571 means that DGMGRL tried to create or save broker files on the destination you designed, but somehow it failed in DGMGRL command line… Read More »How to Resolve ORA-16571: Oracle Data Guard configuration file creation failure
Asymmetric Data Guard Usually we build data guard environments with the symmetric architecture design on primary and standby servers, that is, single-instance to single-instance or… Read More »How to Build Asymmetric Standby Database for Data Guard
We're going to introduce 3 ways that can failover to a standby database at connect-time in this post. Using a Persistent Service Name Using a… Read More »Connect-Time Failover to Standby Database
ORA-00600  Found MRP shutdown with ORA-00600  in alert log of a standby database due to inconsistency of a newly created data file. Wed… Read More »How to Resolve Standby ORA-00600 
Since ALTER SYSTEM ARCHIVE LOG CURRENT is a synchronized fashion of switching redo logs, it has to synchronize the archive log completely to all archive… Read More »ALTER SYSTEM ARCHIVE LOG CURRENT Hangs ?
When I queried the archive gap on the standby database which is a 9i database, I got this error: SQL> select * from v$archive_gap; select… Read More »How to Resolve ORA-01220: file based sort illegal before database is open
As a DBA, you might see many gaps on the standby database in your career like this.SQL> select * from v$archive_gap; THREAD# LOW_SEQUENCE# HIGH_SEQUENCE#---------- -------------… Read More »Sometimes Archive Gap is Just Temporary
Normally and generally, recovery catalog recognizes the databases by DBID which is a unique number among different databases. But there's a problem: the primary database… Read More »How does Recovery Catalog Recognize Databases Which is Which?