Dataguard setup at DR site
Date: Sat, 25 Apr 2009 12:03:57 -0700
Our current standby is using the Oracle 8 way of apply archive logs to standby by manually transfering the files and applying it on standby. Now we want to build a standby at DR location but we want to use Data Guard instead of the current method being followed on the Primary standby.
Is it possible to use the cascade standby approach in this scenario? Transfer from primary to primary standby (which is the old way of doing things) > Transfer from primary standby to DG standby
Also in our database current force logging is not enabled because a
senior dba felt it will cause performance issue and it was shelved
even before it was tested. Based on the real world experience, how
much of a performance impact would it be if force logging is enabled?
But databases that have DG running should have this enabled anyway as
this is a prereq.
The documentation says this.
Performance Considerations of FORCE LOGGING Mode FORCE LOGGING mode results in some performance degradation. If the primary reason for specifying FORCE LOGGING is to ensure complete media recovery, and there is no standby database active, then consider the following:
How many media failures are likely to happen?
How serious is the damage if unlogged direct writes cannot be recovered?
Is the performance degradation caused by forced logging tolerable?
If the database is running in NOARCHIVELOG mode, then generally there is no benefit to placing the database in FORCE LOGGING mode. Media recovery is not possible in NOARCHIVELOG mode, so if you combine it with FORCE LOGGING, the result may be performance degradation with little benefit.
Thank you for your time