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Old 12-08-2005, 03:33 PM   #1
dragonleech
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SMTP/POP3 problems with squid/iptables


I have a new box running fedora core 4 x86-64 with squid and iptables. Whenever I try to send or recieve email through this box I am not able to connect.

The version of squid is 2.5 (I got it by running yum install squid)

I have tried opening up the SMTP and POP3 default ports in iptables but that is not helping.

The proxy is working great I am able to view all websites that I have opened up and it is blocking the ones that I do not want access too.

Thanks for any help

Dragonleech
 
Old 12-08-2005, 03:50 PM   #2
Capt_Caveman
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Can you send mail with the firewall turned off?
 
Old 12-08-2005, 04:10 PM   #3
dragonleech
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I just tried it and I am not able to send with the firewall off or on.

for some more info I have my default gateway set to the IP of proxy server as I want everything routed through it. When I change it back to previous one I am able to send/recieve email.

Once I impliment this I want to have this proxy server as the only box that has direct access to the router so I am planning on setting up the proxy directly attached to the router and then from my second interface card have it connected to the switches of the network.

Thanks,

Dragonleech
 
Old 12-08-2005, 08:16 PM   #4
Capt_Caveman
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Ok. So I'm assuming that you'd like the proxy/gateway to forward mail to and from the mail server, correct? If so, could you post the iptables rules that you are using (make sure to remove any publically routable IP addresses).
 
Old 12-09-2005, 09:31 AM   #5
dragonleech
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you are correct.

I am using webmin to manage the firewall and I just used the option to reset the firewall and set it to allow all traffic. and it is still not allowing email to go through
 
Old 12-09-2005, 12:30 PM   #6
dragonleech
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I have figured some of my problems out. I created a test network with my proxy as the only way to the outside world. I was not able to get of my requests for anything out. I went into the network configuration section of webmin and made some changes to the routing. I am now able to get my HTTP requests out (as I am working behind the proxy right now) but I am still not able to get my SMTP/POP3 packets out. they just time out.

I think that this problem has something to do with routing also as I am able to telnet into the mail server directly from the proxy server but not from behind it.

Thanks,

Dragonleech
 
Old 12-09-2005, 03:28 PM   #7
dragonleech
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I got this working. All I had to do was add a masquarade rule within IPtables for my external interface.

Thanks

Dragonleech
 
Old 12-09-2005, 07:19 PM   #8
Capt_Caveman
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Cool. That's what I was getting to. Nice job on troubleshooting it yourself.
 
Old 09-23-2010, 04:57 AM   #9
madeulook967
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Quote:
Originally Posted by dragonleech View Post
I got this working. All I had to do was add a masquarade rule within IPtables for my external interface.

Thanks

Dragonleech
Dragonleech, i know this is really old but can you let me know the iptable rules you used to get SMTP and POP3 working behind your proxy?


Thanks heaps!
 
  


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