its security would depend, I think, on your firewall setup. Are you using chains or tables? U need to set it up to disallow any nfs connections on anything but your systems. Also, why dhcp? If it is just those two boxes, it is much easier to just go with a static ip. /etc/exports is the file used to setup the exported filesysytem, but to be on the safefguide I would go to www.tldp.org and get the how-to. Better safe than sorry.