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Function documentation Hot Standby Locate the document in its SAP Library structure

Use

In a hot standby system you can quickly switch to a standby database that is running in parallel if the active master database instance fails.

A hot standby system consists of an active master instance and one or more standby components that are installed in a cluster configuration (see Architecture of a Hot Standby System). The hot standby system behaves externally like a normal individual database instance.

In the case of an error in the master instance, a standby component can automatically take over the role of the master component considerably faster than in a standard cluster solution and without the loss of any data. This is ensured by a special failover mechanism of the cluster software.

Prerequisites

You need a cluster solution among others, see System Requirements for a Hot Standby System.

Activities

Set up a database instance as the master component and then add the required number of standby components. When a new standby component is initialized, the memory management system copies the complete content of the master component in a consistent status, for example the status it had at the last savepoint, to the data area of the standby component.

See

·        Database Manager CLI:Setting Up a Hot Standby System

·        Database Manager GUI:Setting Up Master Component (Hot Standby) and Adding Standby Component (Hot Standby)

Master and standby components use the same log area. The standby components are updated automatically at regular intervals using the log entries from the master instance.

 

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