Do not specify something in the script that would prevent the mounting of file systems onto /a during an initial or upgrade installation. If the JumpStart program cannot mount the file systems onto /a, an error occurs and installation fails.
Output from the begin script is deposited in /var/sadm/begin.log.
Ensure that root owns the begin script and that the permissions are set to 644.
You can use custom JumpStart Environment variables in your begin scripts. For a list of environment variables, see “Custom JumpStart Environment Variables”.
Save begin scripts in the JumpStart directory.