How to disable NIS?

I use Casper 4 to backup my computer. That program is not compatible with NIS and I do not want to pay to upgrade to Casper 5.

 

How can I disable NIS while I run Casper 4?

 

I do not care about security since I would disconnect my computer from the internet while I backup my computer.

 

Of course I would enable NIS once my backup is completed.