session_start_notify script
The session_start_notify.cmd script (on Windows) and the session_start_notify script (on UNIX) run on the master server. When a set of backups is due to run, NetBackup calls this script to do any site-specific processing before it starts the first backup. NetBackup passes no parameters to this script.
The scripts are located in the following directories:
On Windows: Install_path\NetBackup\bin\session_start_notify.cmd
On UNIX: /usr/openv/netbackup/bin/session_start_notify