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Q196626: XFOR: Restricting Routing in the Internet Mail Service

Article: Q196626
Product(s): Microsoft Exchange
Version(s): 5.5
Operating System(s): 
Keyword(s): 
Last Modified: 12-JAN-2001

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The information in this article applies to:

- Microsoft Exchange Server, version 5.5 
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SYMPTOMS
========

The Exchange Server Internet Mail Service (IMS) allows you to configure the
server to allow mail relaying. When you enable the Mail relaying in the IMS's
'Routing' property page, all mail will be routed without restrictions. Exchange
Server 5.5 Service Pack 1 allows the administrator to impose restrictions on
routing.

RESOLUTION
==========

To enable these restrictions on routing functionality, follow these steps:

1. Install Exchange Server 5.5 Server Pack 1 (or later).

2. Open the properties on the Exchange Server Internet Mail Service and select
  the Routing page. After the SP1 installation, this page will have an
  additional button called <Routing Restrictions...>.

3. Click Routing Restrictions to bring up a dialog box with additional
  Restrictions.

MORE INFORMATION
================

Exchange Server 5.5 Service Pack 1 adds "Routing Restrictions" to the Internet
Mail Service. This allows the administrator to specify who can relay mail off of
your Exchange Server computer.

The following Restrictions have been added:

Specify the hosts and clients that can route mail when the following conditions
have been met.

- Hosts and clients that successfully authenticate:

  Messages sent from hosts and clients with valid logon information are relayed.

- Hosts and clients with these IP addresses:

  Messages sent from host whose IP addresses and subnet mask fall within the
  range to be allowed to relay.

  To only allow a single host or client, enter in the format, IP=>full IP
  address of client< (i.e 1.1.1.1), MASK=255.255.255.255

  To allow a range of IP address to relay, enter in the format, IP=>scope to
  allow< (i.e 1.1.1.0>, MASK=255.255.255.0. This will allow the address
  range of 1.1.1.1 - 1.1.1.254 to relay.

- Hosts and clients connecting to these internal addresses

  Messages sent by hosts and clients that connect to the specified IP address on
  the Microsoft Exchange Server computer are relayed. This allows multihomed
  servers to restrict message relay based on the IP address to which the client
  connects. If you select this option, you must disable IP forwarding on the
  Networking property pages in Control Panel.

Specify the hosts and clients that can NEVER route mail.

- Messages sent from the specified IP addresses and subnet mask are NOT
  relayed.

Additional query words: rerouting spam spoof IMS SMTP restrict restrictions

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Keywords          :  
Technology        : kbExchangeSearch kbExchange550 kbZNotKeyword2
Version           : :5.5
Issue type        : kbprb

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