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Re: woody firewall broken?



> > Maybe, I'm not sure, some remote MTAs, for example smtp.navegalia.com,
uses
> > UDP connections. You can try "telnet smtp.navegalia.com 25" behind a
> > firewall which filter the udp connection.
>
> Eh?
> $ telnet smtp.navegalia.com 25
> Trying 212.73.32.155...
> Connected to smtp.airtel.net.
> Escape character is '^]'.
> 220 ESMTP service
>
> It answers TCP, I know of no MTA (or MUA) that uses UDP...

Well, I have removed the iptables rule allowing the UDP/25 packets and it
works OK. It seems you are right again.


> If you're having firewall problems then most likely:
> *) TCP port 25 is not allowed

> *) TCP port 113 (AUTH) is not allowed (it should be REJECTED, a
>    DROP will result in some remote MTA timeouts as they try to
>    issue AUTH requests)

I have added the iptables filter:
iptables -A FORWARD -p tcp -d 194.224.7.3 --dport 112 -j REJECT



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