You are absolutly right. Actually, the command is correct, and also working fine in my environement, so I suspect also that some options by be missing in the kernel. Eric > This is not really true ... > > According to the iptables man page, DNAT is valid only in the OUTPUT > and PREROUTING chain of the nat table. SNAT is only valid in the > POSTROUTING chain of the nat table. > > It could be a missing kernel option ... > > Frederic Gobin > > Am Dienstag, 29.04.03 um 09:49 Uhr schrieb SaVaGE: > > > Op dinsdag 29 april 2003 09:23, schreef netfilter_user: > >> Hello everyone, > >> > >> this is my problem: > >> My LAN is connected to Internet via Linux machine with 2 interface ( > >> ppp0 - for internet and eth1 for local net). I need to connect from > >> local host, service that is running on port 23073 and 23083 UDP in > >> internet. For this i wrote afew rules with PREROUTING but when I start > >> script with rules below i receive: > >> > >> Bad argument `PREROUTING' > >> Try `iptables -h' or 'iptables --help' for more information. > >> Bad argument `PREROUTING' > >> Try `iptables -h' or 'iptables --help' for more information. > >> > >> > >> iptables -t nat -A PREROUTING -p udp -d 80.50.60.185 --dport 23073 -j > >> DNAT > >> --to-destination 192.168.1.2 iptables -t nat -A PREROUTING -p udp -d > >> 80.50.60.185 --dport 23083 -j DNAT --to-destination 192.168.1.2 > >> > >> iptables -A FORWARD -p udp -d 192.168.1.2 --dport 23073 -j ACCEPT > >> iptables -A FORWARD -p udp -d 192.168.1.2 --dport 23083 -j ACCEPT > >> > >> What maybe a reason of this msg? > >> Im using slackware 8.1 with iptables 1.2.6a > > > > This behaviour is correct NATting is done on the POSTROUTING table !!!! > > > > > > Pascal (PC-Secure Dutch security service) > > > > > >
