In WebLogic 11.1.1.1 the boot.properties file was stored in the $MW_HOME/user_projects/domains/[domain] directory. It would be read at startup and there would be no requirement to enter username and password.

In later releases the location has changed to

$MW_HOME/user_projects/domains/[domain]/servers/[managed_server]/security

In most instances you will need to create the security directory

If you want to specify a custom directory add the following to the startup scripts for the server.

-Dweblogic.system.BootIdentityFile=[loc]/boot.properties

create a boot.properties file using the following entry

username=<adminuser>
password=<password>