A boot identity file contains user credentials for starting and stopping an instance of WebLogic Server. An Administration Server can refer to this file for user credentials instead of prompting you to provide them. Because the credentials are encrypted, using a boot identity file is more secure than storing unencrypted credentials in a startup or shutdown script. If there is no boot identity file when you start a server, the server instance prompts you to enter a username and password. The boot identity file can be different for each server instance in the domain.
This video demonstrates How to create Boot Identity File in Oracle Fusion MiddleWare:
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