As far as I can figure out, the following: iptables -N mymap macipmap for ip in 192.168.1.`seq 6 75`; do for mac in xx:xx:xx:xx:xx....75 MACs; do iptables -A mymap $ip:$mac iptables -T mymap $ip -j ACCEPT done done should yield the same result and be faster than: for mac in xx:xx:xx:xx:xx....75 MACs; do iptables -t mangle -A PREROUTING -i eth1 -m mac --mac-source \ ${mac} -j ACCEPT done iptables -t mangle -A PREROUTING -i eth1 DROP iptables -t mangle -A PREROUTING -i eth1 -m iprange ! --src-range \ 192.168.1.1-192.168.1.74 -j DROP but I am not sure of this. The drawback of using the hash is that the MACs must match the IPs in dhcpd.conf, but this can be dealt with. Is there no -m flag before macipmap? Can someone with experience weigh in on this, both concerning speed and correctness? ipset doesn't seem to be what I need here. Thanks, Jason -- To unsubscribe from this list: send the line "unsubscribe netfilter" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html