When using the NetBackup Database Extension GUI, SQL Server security is satisfied. This is based upon either your current Windows account (if you use integrated security) or a SQL Server-based user ID and password.
When the NetBackup scheduler is used, backup operations that are launched from a daemon process called the NetBackup Client Service. You must ensure that the Client Service has SQL Server privileges to perform backup and restore operations. If you use integrated security, you must ensure that the NetBackup Client Service specifies a Windows account that has been granted SQL Server administrative privileges.