Creating a new SLP

Hello

I am a little new to the backup environment. I would like to know if some one give me command for creating a new SLP

i know it is nbstl SLPNAME -add ...................

But then i am lost. i know how to create it using GUI. But for some reason my Storage units do not load in my master.

 All policies and SLP's load but Storage units and storage unit groups do not load.

I guess now i have two questions. Any help will be appreciated.

Best