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Postprocessing And Remarks
  • If not yet done, now is the time to apply the parameter adjustments to the master database, as mentioned in the first section
  • Your new standby database is created, but not yet automatically recovering. So you need to issue the ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DISCONNECT; command at the sqlplus prompt, logged in as SYSDBA
  • Though starting with 10g, Oracle automatically detects a standby database when the STARTUP command is issued, and opens it read only - it again does not start the managed recovery automatically. So you still need to take care that this is done after server restart.
  • Optionally, you may want to create STANDBY LOGFILE GROUPs (see below).
Concerning the standby logs, let me quote a part of a Metalink documentation here:

"Standby redo logs are necessary for the higher protection levels such as Guaranteed, Instant, and Rapid. In these protection modes LGWR from the Primary host writes transactions directly to the standby redo logs. This enables no data loss solutions and reduces the amount of data loss in the event of failure. Standby redo logs are not necessary if you are using the delayed protection mode."

That is, by default we don't need them (since we use the deferred method: Redo log is applied to the standby after the primary has archived it, which means a certain delay). If your concern is to have the standby immediately applying redo information as soon as it is generated on the primary instance, i.e. without any delay - then you will need the standby logs. But remember in this case to configure them on both, the primary and the standby database - though they are not used on a primary instance, after a SwitchOver/FailOver the primary becomes the standby and should be prepared for this task.
There are some more things to take care of if you are going to configure standby logs - too much for our little article, so please refer to the Oracle documentation. Two hints I give you: One is the command, ALTER DATABASE ADD STANDBY LOGFILE, so you know what to look for. The other is a Metalink document on this topic, see note 180031.1.
RMAN Framework
Most of these steps can be automated using the RMAN wrapper from the DBAHelper framework. These are:
  • Automatic backups using the FRA
  • Of course also managing those backups, restoring, recovering...
  • Starting with v0.2.2: Guided creation of a standby database
The last mentioned feature will guide you step by step through what was explained in this article. Many things as creating a backup, creating a copy of the controlfile, turning on the managed recovery, will be done automatically when you answered the corresponding question with yes. However, some steps must still be done manually, as editing the configuration files, and copy files to the correct locations.
General remarks
On the standby database, we cannot use Oracles DBConsole (since this one always places its repository in the local database itself, which is read only in case of a standby database and thus cannot be used; there is no way to place the repository in a different database). So if you want an interface like that for administration, you will need to setup Grid Control. But this is a topic for another article.
Further readings
  • MetaLink Note 789370.1: Creating physical standby using RMAN duplicate without shutting down the primary
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