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New Member

Access-List Configuration for Mail Server

Hi Guys

I have a little bit of problem setting the access-list on my Router 2801. I have a mail server, after applying the access-list i cant neither send mail nor receive mail for some reason. I am confused about this behaviour.

I have an example of the config i have setup. The mail server is am SMTP Gateway (MailMarshal). Would appreciate if some one has any suggestion about it.

Port forwarding wont work, because i wont be able to send out mail then.

I am not blocking any traffic going out.

NAT FOR MAIL SERVER

ip nat inside source static <inside ip> <outside ip>

ACL FOR SMTP PORT

access-list 110 permit tcp any host <outside ip> eq 25

APPLYING ACL

Interface Faste 0/1

*** Connect's to the ISP ***

ip access-group 110 in

Thanks in advance

5 REPLIES

Re: Access-List Configuration for Mail Server

I think you need to also allow the TCP established sessions when you configure the ACLs. You may want to try access-list 110 permit tcp any any established

New Member

Re: Access-List Configuration for Mail Server

Thanks Ganesh

My new access-list

access-list 110 permit tcp any host eq smtp

access-list 110 permit tcp any any established

still no help ...

the think i am confused about it in if there is a problem with the access-list it should be mail only coming in.

but i can't send mail out too.

Thanks

Re: Access-List Configuration for Mail Server

Can you post the config after removing any sensitive info.

That would help quickly identifying the problem.

New Member

Re: Access-List Configuration for Mail Server

Hi Mate,

Try this

"ip nat inside source static tcp 25 25 extendable"

Plus, you are sourcing traffic from the server out and also revceiving, so add the following:

"access-list 110 permit tcp any eq 25 host "

And, you will be able to send mail as the port forwarding is bidirectional.

BR

New Member

Re: Access-List Configuration for Mail Server

Thanks for all you help guys..

The issue was with the SMTP gateways,,, it was doing a Reverse dns lookup, And a dns port heeded to be allow through...

Thanks for all you help ....

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