Client Support - Using Microsoft Exchange™ Server with
your Ashton ITC Virtual Server (Corporate & Enterprise)

1.0 Introduction

Microsoft Exchange is an e-mail server that can be used to handle local (Intranet) email. It can also be configured to send and receive outgoing (Internet) mail on demand (dial on demand). For more information on the Exchange Server, please see:

http ://www.microsoft.com

Not only can Microsoft Exchange be used as a local mail server to handle your intranet mail, but it can also be configured to send and receive mail to and from the Internet. Typically, a dedicated Internet connection, including the purchase of a high speed line (T1), a router, a CSU-DSU, a firewall, DNS Servers, etc, would be required in order for your Local Area Network (LAN) to send and receive Internet mail. The capital required to make such a commitment, in most cases, is far too high and prohibits small to medium sized businesses from integrating the Internet into their LAN or Intranet.

However, with the Microsoft Exchange server, you can have the server dial-up to your local ISP on demand, then connect to the mail service on your Ashton ITC Virtual Server and download any stored mail. This allows you the ability to have continuous e-mail support on your local intranet where traffic is heavier, in addition to being able to send and receive e-mail to and from the Internet on a more periodic basis. You should be aware that this solution is only available when using our Corporate or Enterprise Server option.

Because your Ashton ITC Virtual Server is always connected to the Internet, it is always available for incoming mail messages and can store (or queue) these messages for you until you are ready to retreive them. The ability of the Microsoft Exchange server to perform dial-on-demand e-mail retrieval allows you to take advantage of the lower prices of a dial-up connection, providing a more affordable Internet mail solution for your company. The information provided here should be easily adaptable for any other Mail Server, such as Novell’s Workgroup Server.

The diagram below illustrates the theory behind the process. You and your fellow employees are located on your LAN or Intranet at Your Office. You use a dial-up connection through Your ISP to surf the web, read news, download files, and remotely administrate Your Virtual Server. You may have previously had both an internal LAN mailbox and a POP or IMAP mailbox on your Virtual Server.

Using the Microsoft Exchange server (or equivalent software) you can now queue your Internet mail on your Virtual Server and instruct Microsoft Exchange to periodically connect to the Internet, download the mail from your Virtual Server, and then distribute it to your local area network mailboxes.

2.0 Configuration

2.1 Client Side

On the client side, you will need to configure the Exchange Server to dial-up to the local ISP on demand. How to do this should be documented in your Exchange Server manuals. A great additional resource is provided by Simpler Web Inc. (http://www.swinc.com). In essence you need to:

1. Configure your RAS/DUN.

a. You will need an entry in the phonebook that makes an automatic connection to your local ISP at the intervals you specify.

b. You need a TCPIP hostname and domain configured in Control Panel/Networks/TCPIP

2. Configure the Exchange SMTP service. For Exchange 5.0 this will be the Internet Mail Service. This should be pointed to the SMTP server for your Ashton ITC Virtual Server (smtp.yourdomainname.com).

3. If necessary, configure the SMTP Addresses for your users. You can globally configure this using the Site Addressing configuration page, or you can use Directory Import to configure individual addresses. This would only be necessary in the event you had multiple users in your "Intranet" that had a different Ashton ITC Virtual Server.

4. Now, you need to configure the server to tell the mail server to dequeue mail. You will need to configure your Exchange Server to run the "etrn" command. This command tells the Ashton ITC virtual server to attempt to resend your queued mail. A script written by Simpler Web Inc. will help set up your Exchange server to do this:

http ://www.swinc.com/files/dequeue.exe

In essence, you’re connecting to your smtp port and telling the mail server you want to dequeue your mail. For those people not using MS Exchange, you could write your own script. Here is an example UNIX shell script that would do the same (substitute your domain name for my-domain.com).

#! /bin/sh
# We got this from:
# http://www.swinc.com/resource/exch_smtp.htm
# Send ETRN command to sendmail 8.8.x
# written by Andy Rabagliati andyr@wizzy.com
#
telnet mail.my-domain.com smtp «SMTP_EOF
ETRN my-domain.com
QUIT
SMTP_ECE
#
# End of Shell script
#

Or alternately

#! /bin/sh

OURSITE=exchange.isp.com
MAILSERVER=mail. sfpsi. com
TELNET= /usr/bin/telnet
PORT=25

echo "etrn $OURSITE" |$TELNET $MAILSERVER $PORT exit 0

2.2 ISP configurations

You must have a dedicated IP address for the MS Exchange Dial-up solution to work. There is no other alternative to this (currently). This will require either that you:

1. Purchase a dedicated modem at your ISP’s modem bank that only you connect to and that is assigned your dedicated IP address

OR

2. Your ISP has the ability to detect when you dial in and can assign that dial-in your dedicated IP number.

The second thing your ISP must do for you is map a domain name to that dedicated IP address. For example, if your local Internet Service Provider has a domain name "myisp.com" and they were going to give you an IP address of 222.222.222.222, you want them to map 222.222.222.222 to a unique instance of my-isp.com. As an example:

exchange.myisp.com mapped to 222.222.222.222

Here is an example dns entry for this:

IN SOA nsl.my-isp.com. hostmaster.my-isp.com.
       1997072802 ; Serial number
       86400    ; Refresh
       7200                 ; Retry
       2592000  ; Expire
       172800 )    ; Minimum TTL

NS     NS1.MY-ISP.COM.

NS     NS2.MY-ISP.COM.

A      222.222.222.1
MX 10  my-isp.com

exchange A 222.222.222.222

Another alternative would be to use your Ashton ITC domain name in the zone file above instead of the name "exchange". For example if you have an Ashton ITC Virtual Server and your domain name for the Virtual Server was xyz.com

You might have your ISP set up their dns zone file to point to

 

xyz A 222.222.222.222

Now, all mail sent to xyz.my-isp.com would resolve to the dedicated IP address 222.222.222.222

This is important, you must have a dedicated IP address (one that is uniquely assigned to your Exchange Server), and you must have a domain name pointing to that IP address for the MS Exchange solution to work.

 

2.3 Ashton ITC

This one is easy. Just one step:

1.Mail support@ashtonitc.com and have us edit your zone file for your Ashton ITC domain.You will want us to add an additional mx record into the zone file. If you had your ISP configure their DNS server as outlined above, and the name of your Ashton ITC Virtual Server was "xyz.com", the entry would be as follows:

MX 10  xyz.my-isp.com
MX 20  xyz.com

MX stands for "Mail Handler". The Internet knows how to send mail to your domain by looking at these MX records. In this zone file, we are saying that the Exchange Server (xyz.my-isp.com) has the first priority for mail delivery (MX 10). Your Ashton ITC virtual server (xyz .com) has second priority (MX 20). If mail can’t be delivered to the first priority mail server it is sent to the second priority mail server. Since your first priority mail server is generally not going to be connected to the Internet at the time someone sends you an e-mail, the Ashton ITC virtual server will receive e-mail for your domain name. Then, when you log in with your Exchange Server, your Ashton ITC virtual server will send your Exchange Server your mail.