$ sudo apt-get update
$ sudo apt-get install fai-nfsroot 

fai-nfsroot is installed in your system.

Make ensure the fai-nfsroot package were installed using the commands given below,

$ sudo dpkg-query -l | grep fai-nfsroot *

You will get with fai-nfsroot package name, version, architecture and description in a table

fai-nfsroot package basic information: