1 - Install NFS Service on host typing:
your slackware linux probably already have a version of nfs"utils installed, but if it doesn't you can get it downloading the nfs-utils from: 
then as root: #installpkg nfs-utils-1.0.7-i386-1.tgz
2 - Setup exports typing:
$sudo kedit /etc/exports
and add the following line:
3 - Restart the NFS server:
$sudo /etc/rc.d/rc.rpc restart $sudo /etc/rc.d/rc.nfsd restart
Now the host is ready to use NFS.
1 - Run LTIB configuration typing:
2 - On first page menu, go to "Target Image Generation -> Options".
3 - Select the option NFS only and exit LTIB configuration to compile with the new configuration.
4 - LTIB should start new compiling and create a new Linux image on /<ltib instalation folder>/rootfs/boot/zImage
5 - Copy the created image on /<ltib instalation folder>/rootfs/boot/zImage to /tftpboot/zImage
6 - The system is ready to run with NFS. The root file system on target will be located on host on /<ltib instalation folder>/rootfs/