Basically you have 2 fairly easy options here, depending on the firewall:
1) With most firewalls you can forward certain port numbers to an internal
machine, it's usually referred to as "port mapping" or "internal mapping".
Most NAT devices support this, including Pipeline and SonicWall routers
(though I don't recommend it on the Pipeline, it's very flaky), as well as
the NAT that is built into Windows 2000. If the firewall supports internal
mappings, then map port 25 inbound on the firewall's external IP address to
port 25 on the internal IP address of the exchange server. I don't really
see the need for ETRN since once you define the external address of the
firewall in your hosts file, mail will be delivered automatically upon
receipt by the IMail server. In fact, if the firewall supports internal
mappings, you don't even really need the IMail server at all. Just point the
MX record to the external IP address of the firewall and it will handle the
rest.
2) If the firewall does not support internal mappings, there is a program
called Autodialer that will retrieve email from a POP mailbox and convert it
back to SMTP for a local mail server. As the name implies it is can also be
used with dial-up modem connections, but it's just as easy top use through a
NIC. In this scenario, you could use the "nobody" alias on the IMail server
to catch all email for the domain and install Autodialer on the Exchange
server. You can then program Autodialer to retrieve mail every 30 minutes or
so. Again, no need for ETRN. Autodialer costs around $80 and it works with
almost any SMTP mail server on NT (I've used it with NTMail, IMail, and
Exchange).
In either configuration there is no reason to confuse things with "fake"
domain names since each mail server is isolated from the other by your
firewall.
Mike Perdue
WebMaster
The Grizzard Agency - An MSGi Direct Company
-----Original Message-----
From: Dave Wilson [mailto:[EMAIL PROTECTED]]
Sent: Thursday, May 18, 2000 12:12 PM
To: [EMAIL PROTECTED]
Subject: [IMail Forum] Gateway through firewall to Exchange using ETRN -
help
Hi all,
I'm having some difficulties in configuring an Imail server for a client.
The set up at the client is as follows:
Leased line connection recently installed;
Gnat Firewall;
Imail server outside firewall with public IP;
Exchange server inside firewall (Private IP - 192....)
NO internal DNS.
Prior to having leased line, the client has been using their Exchange server
for internal mail only and using one of our in-house Imail servers via the
internet using a dial-up connection to another ISP.
I thought it would be appropriate to configure their new Imail machine to
store and forward all their mail to their internal Exchange Server using
ETRN, but am stuck on a technicality. Basically, as their internal Exchange
server doesn't use a FQDN, and is using an internal IP, I can't figure out
how I am to write the MX records and host files to make this work.
The exchange server has been set up to recognize a pseudo-domain e.g.
innerdomain.com (not registered with Internic) and I have configured their
Imail server as outerdomain.com (Fully registered and qualified domain).
My current thinking is that maybe I should set up internal DNS for the
client but not sure how to set this up correctly for this situation and also
not sure if I'm close to the mark or going totally the wrong direction.
Any help would be much appreciated.
Dave
Dave Wilson
Internet Technology Manager,
BizNet Solutions
<Allaire Premier Partner>
Co-Founder CFUG Ireland
http://www.cfug.ie
224, Lisburn Road
Belfast BT9 6GE
Tel: 02890 225 776
Fax: 02890 223 223
web: http://www.biznet-solutions.com
email: [EMAIL PROTECTED]
Please visit http://www.ipswitch.com/support/mailing-lists.html
to be removed from this list.
Please visit http://www.ipswitch.com/support/mailing-lists.html
to be removed from this list.
