Now that you have created a domain, it is important to understand how to back up critical domain data in case of a failure. You can archive domain configurations in various ways — by using periodic backups to tape or fault-tolerant disks, or by manually copying files to another machine. Having a backup allows you to restart the Administration Server on a different machine in case of failure, or restart a Managed Server in the absence of the Administration Server.
The three resources to back up are the configuration data for the domain, the security data for the domain, and, of course, any deployed applications.
The most critical aspect of a domain configuration is the config.xml file that holds the configuration for the entire domain. The config.xml file usually is stored in the root directory of the domain. Although you can start a Managed Server without it in certain circumstances, it is necessary for the overall administration of the domain.
The file usually is accompanied by a useful secondary backup, config.xml.booted. This file is created only after the Administration Server has successfully started up. So, for instance, if you have made severe changes to the configuration for a domain, and the Administration Server no longer starts up, you can overwrite the config.xml file with the config.xml.booted file, and thereby restore the domain to its last known successful startup configuration. This is very useful while you are experimenting with ...