From: Jason Opperisano Subject: Re: mails not going thru' Date: Sat, 7 May 2005 10:47:36 -0400 Message-ID: <20050507144736.GA31683@bender.817west.com> References: Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: netfilter-bounces@lists.netfilter.org Errors-To: netfilter-bounces@lists.netfilter.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: netfilter@lists.netfilter.org On Sat, May 07, 2005 at 10:14:49AM +0500, varun_saa@vsnl.net wrote: > *filter > :FORWARD ACCEPT [0:0] > :INPUT DROP [0:0] > :OUTPUT ACCEPT [0:0] > -A INPUT -s 127.0.0.1 -j ACCEPT > -A INPUT -p tcp -m tcp -i eth1 --dport 3128 --sport 1024:65535 -j ACCEPT > -A INPUT -p udp -m udp -i eth1 --dport 3128 --sport 1024:65535 -j ACCEPT > -A INPUT -s 62.0.0.0/255.0.0.0 -i eth0 -j REJECT > -A INPUT -p tcp -m tcp -s 217.81.0.0/255.255.0.0 -i eth0 -j REJECT > -A INPUT -i eth0 -j DROP > -A INPUT -p tcp -m tcp -i eth1 --sport 80 -j DROP > -A INPUT -m state -i eth1 --state ESTABLISHED,RELATED -j ACCEPT > -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT > -A FORWARD -p tcp -i eth1 -o eth0 --dport 25 --sport 1024: -j ACCEPT --syn > -A FORWARD -p tcp -i eth1 -o eth0 --dport 110 --sport 1024: -j ACCEPT --syn > -A FORWARD -p tcp -i eth1 -o eth0 --dport 1863 --sport 1024: -j ACCEPT --syn > -A FORWARD -p tcp -i eth1 -o eth0 --dport 5050 --sport 1024: -j ACCEPT --syn the policy of your FORWARD chain is set to ACCEPT, so even if there's traffic you haven't accounted for in these rules--it will still be allowed through. you have a rule that allows SMTP (TCP 25) out--so i bet if you type: telnet 64.233.185.27 25 which is the IP of gmail's preferred MX, you'd get connected. if you're FORWARD policy was DROP, i'd say that the reason you can't send mail from a client machine is because you have no rule allowing DNS traffic out: -A FORWARD -i eth1 -o eth0 -p udp --sport 1024: --dport 53 -j ACCEPT -A FORWARD -i eth1 -o eth0 -p tcp --syn --sport 1024: --dport 53 \ -j ACCEPT but since those packets will be accepted by the chain policy, my only guess is that you do not have any valid DNS servers configured on your client machines--on a *nix box: cat /etc/resolv.conf -j -- "Richie: Mom, uh, I really like Potsy. Mrs. Cunningham: Well, Potsy's a nice boy, dear. Why shouldn't you like him? Richie: No, I mean... I REALLY like Potsy. Mr. Cunningham: We heard you the first time, son, you've got a homosexual attraction to Potsy." --Family Guy