Nick Smith wrote:
yes they can get mail but not send mail, the reason for relaying through comcast.net is because if they relay through their own domain it gets marked as spam etc, that whole DUL thing, they only (cheapest) way to get it working was to relay through comcast, my client is running *cough* exchange 2000, but if i can offer a linux alternative that will work, im sure i can get them to switch, i am running a postfix/courier-imap setup for my domain at home on the comcast network and they havnt shut me down as of yet, but i think its only a matter of time, which is why i want to find out now if there is a way around this.
I'm still confused about the network architecture and where these servers actually live, but as I mentioned, the policy is to block port 25 connection attempts, so as long as you have control of a server sitting outside the comcast domain, you can direct SMTP traffic to another port, say, 2500. This will get through the ISP firewall. A simple way to do that on the server would be:
iptables -t nat -A PREROUTING -p tcp --dport 2500 -j REDIRECT --to-ports 25
_k
-- [email protected] mailing list
