NFS server can be installed with the command:

apt-get install nfs-kernel-server

After the installation is completed, you will have to create NFS share.

NFS share is just a directory that can be mounted from remote clients.. Create the directory to be shared over NFS with the command mkdir /nfsroot

 
After creating the directory, open the file /etc/exports 

nano /etc/exports

This file contains a list of NFS shares, IP addresses they can be mounted from, type of access (read-only or read-write), and other sharing options. Assume that your IP subnet with the servers for Bare-Metal Restore is 192.168.1.0/24. Add to /etc/exports the following line:

/nfsroot 192.168.1.0/24(ro,no_root_squash,no_subtree_check)

Save the file and run the command:

exportfs -r

Then you can start NFS service by executing the following command: /etc/init.d/nfs start

To make sure your NFS share is visible to the client, run the following command on NFS server: showmount -e