Oracle B32100-01 Benutzerhandbuch

OracleAS Disaster Recovery: Introduction

Oracle Application Server Installation Guide

middle tiers. In an asymmetric topology, the number of instances required on the 
standby site are fewer than the number on the production site and the number of 
instances required on the standby site must be the minimum set of instances required 
to run your site in the event of a switchover or failover operation. 

As a small variation to this environment, you can set up the OracleAS Infrastructure 
on the production site in an OracleAS Cold Failover Cluster environment. See 

 for details.

For these supported topologies, OracleAS Guard will be installed in every Oracle 
home on every system that is part of your production and standby topology 
configured for the OracleAS Disaster Recovery solution. 

OracleAS Guard can be installed as a standalone install kit located on OracleAS 
Companion CD #2. See 

 for more information about 

when this standalone kit should be installed.

 shows an example symmetric OracleAS Disaster Recovery environment. 

Each site has two nodes running middle tiers and a node running OracleAS 
Infrastructure.

For OracleAS Disaster Recovery to work, data between the production and standby 
sites must be synchronized so that failover can happen very quickly. Configuration 
changes done at the production site must be synchronized with the standby site.

You need to synchronize two types of data. The synchronization method depends on 
the type of data:

■

Use Oracle Data Guard to synchronize data in the OracleAS Metadata Repository 
databases on the production and standby sites. You can configure Oracle Data 
Guard to perform the synchronization.

■

Use the backup and recovery scripts to synchronize data outside of the database 
(such as data stored in configuration files).

See the Oracle Application Server High Availability Guide for details on how to use Oracle 
Data Guard and the backup and recovery scripts.