Background documentationWhat Happens When the Master Database of a Hot Standby System Fails? Locate this document in the navigation structure

 

If the master database of the hot standby system fails, a standby database automatically assumes the role of master database. The downtime is short (a restart of the master database would take much longer, for example).

The cluster software constantly monitors the master database of the hot standby system.

  1. When the master database fails, the cluster software notifies one of the standby databases that it must take over from the master database.

  2. The new standby database adopts the virtual server name of the old master database, with which the hot standby system is addressed externally.

  3. The storage system gives the new master database write authorization for the entire log area.

  4. The new master database imports the remaining log backups from the old master database and repeats the respective data changes.

  5. The database system transfers the new master database from the STANDBY to the ONLINE operational state.

Once you have eliminated the error in the master database, you can add the old master database as a standby database to the hot standby system.