I have a number of web servers on which I've set up iptables as the firewall, this is working great. However, I also have a dedicated file server running NFS and I need to firewall this machine as well. As I understand from looking around, setting up iptables with NFS can be a tricky thing. Since I can freely choose the software I run on my servers I can easily change to another firewall.
If it makes any difference, running an NFS behind a firewall, what firewall software do you recommend instead iptables?