Hi Julien, Julien <dyna@xxxxxxxxxxxxx> wrote: > Hi, > > I have been trying for a few days now to route mail traffic on a=20 different connection than rest of traffic using iproute2, I already did=20 some posts regarding this problem, and thanks to help of guys here and=20 in the lartc mailing list I succedeed to have a little improvement. > > Here are the box infos : > > Slackware 9.1 (Linux 2.4.22) > Two dsl connections via pppoe > > I only care about locally generated mail traffic but I didn't succeed=20 making it as the mta level. > > I did : > iptables =E2=88=92A OUTPUT =E2=88=92i eth0 =E2=88=92t mangle =E2=88=92p t= cp =E2=88=92=E2=88=92dport 25 =E2=88=92j MARK =E2=88=92=E2=88=92set=E2=88= =92mark 1 > echo 201 mail.out >> /etc/iproute2/rt_tables > ip rule add fwmark 1 table mail.out > ip route add default via [Second's ISP Gateway] dev ppp1 table mail.out > Why not use the ROUTE target ? Let's say your normal flow goes through ppp0 by default. def_int=ppp0 iptables -t mangle -I OUTPUT -o $def_int -p tcp --dport 25 -j ROUTE --oif ppp1 --continue So now, all traffic generated from the computer itself will use ppp1 as the outgoing interface. Do not forget the --continue which means the packet will continue traversing other rules. > In order to make packets go out with correct source ip address : iptables -t nat --append POSTROUTING -p tcp --dport 25 --jump SNAT=20 --to-source [Second's ISP external IP] > Correct. > The current situation : > I can see with tcpdump packets going out, and back but if I do telnet=20 someisp.com 25 I see nothing in the terminal. > Are you sniffing on ppp1 ? Did you enable NAT of local connection ? > I really don't know what can be wrong and found no answer neither in the=20 > mailing list archive, in the lartc howto or in the advanced routing howto= . > I can actually not answer. Please provide more details such as related Conntrack entries, commands you executed to troubleshoot, etc. -- Samuel Jean SysAdmin & NetAdmin at cookinglinux.org -- Samuel Jean SysAdmin & NetAdmin at cookinglinux.org
