On Jan 20, 2008 9:54 AM, ankush grover <ankushcentos at gmail.com> wrote: > Hi Alain, > > Thanks for replying to my question. > > > > My understandin is: > > You are load balancing your outgoing traffic.... > > Yes, load balancing outgoing traffic > > > > > > route add $smtpserver1 netmask 255.255.255.255 gw $publicip1 > > > route add $publicip1 gw $gw1 > > > > You are trying to force the GW for smtpserver1, but .... > > > Yes, we are trying to the force the gateway for smtpserver1 and > smtpserver2 . As both the smtpservers will go through specified ISPs. > > > > Some more iptables rules which ban sending mails from different > > > vlans/lans directly to public ips (both 1 and 2) > > > $IPTABLES -A INPUT -p tcp -s $lan1 -d $publicip1 --dport $SMTP -j DROP \ > > > > > > > > > $IPTABLES -A INPUT -p tcp -s $lan2 -d $publicip1 --dport $SMTP -j DROP \ > > > > > > > > > $IPTABLES -A INPUT -p tcp -s $lan3 -d $publicip1 --dport $SMTP -j DROP \ > > > > > > > > > Same rules we have for publicip2. > > > > > > But still we are not able to send emails from the $smtpserver running > > > in the local lan to outside. Our requirement is like this smtpserver1 > > > which is running postfix should only send/receive emails through > > > publicip1 and smtpserver2 which is also running postfix should > > > sends/receive mails through publicip2. > > > > > > We are able to receive emails both the public ips on the respective > > > smtp servers but when we are sending emails to outside world it is > > > sometimes going through both the public ips from a single smtp server. > > > > ... it doesn't work. > > > > I had a similar problem. > > I have create rules in the mangle INPUT table to 'mark' packets , for example: > > > > 0 for packet that must be load balanced > > 1 for packet that must go through first ISP > > 2 .... for the second ISP > > > > Then in my routing rules, I use the mark to use one or another routing table. > > > > Can you mail me an example that will be very helpful for me. Sorry dont have these config anymore. Here are some hint I can remember, (without looking the correct syntax in the doc) # create the routing tables ip route add default gw dev eth1 table 1 ip route add default gw dev eth2 table 2 #redirect to the correct table regarding the mark ip rule add mark 1 table 1 ip rule add mark 2 table 2 # to set the mark iptables -t mangle -A PREROUTING $YOURCONDITION[1..n] -j MARK --set-mark [012] I was not using dynamic balancing like you but static balancing depending on the source IP. Hope this help regards > > > Thanks & Regards > > Ankush > -- Alain Spineux aspineux gmail com May the sources be with you