Log In

Come Join Us!

Are you a
Computer / IT professional?
Join Tek-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Tek-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Exchange internet mail connection through router

Exchange internet mail connection through router

Exchange internet mail connection through router

How does one connect Exchange server to the internet through a NAT router like the Acsend Pipeline 50? Microsoft says it can only be outgoing, (Q193863) but that doesn't make sense - a periodic connection to the ISP is similar but the RAS can't see the router. Any help would be appreciated.

RE: Exchange internet mail connection through router

The problem is that outbound for NAT is easy since the outbound translated address is real even though the inside is not. Since SMTP is a true point-to-point system (meaning smtp mailers need to be able to see the end ip address of the smtp acceptor)you would need something on the router to accept the inbound SMTP that is a legal address since the ip of the actual accepting smtp system is not legal. What you may be thinking of is an ESMTP system where the mail destination is actually at an isp and as the connection is made the esmtp mailer sends it down. This works since point-to-point, ip addresses are all legal since the destination is at the ISP and not behind your NAT. The option here is to check and see if the router will do smtp proxy where the end distination is the legal side of the NAT. The proxy then re-wraps the packets with new IP detinations and sends it to the internal smtp server.

RE: Exchange internet mail connection through router

To refer to your networking problem and avoid the exchange issue the following may help.
I am not sure of the config on an Ascend Pipeline router but I do know that on a CISCO you can map a port on the router to an internal IP address. This is the format in Cisco IOS 11.3
"ip nat inside source static tcp 25 25 extendable no-alias"
Where is a valid IP and is not.
This is assuming you always get the same address from your ISP for the router.
This should allow the ISP smtp machine to communicate with the internal server since it will hit a valid IP and port which the router refers to your internal server.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Tek-Tips Forums free from inappropriate posts.
The Tek-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Tek-Tips forums is a member-only feature.

Click Here to join Tek-Tips and talk with other members! Already a Member? Login

Close Box

Join Tek-Tips® Today!

Join your peers on the Internet's largest technical computer professional community.
It's easy to join and it's free.

Here's Why Members Love Tek-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close