DOCUMENT:Q152503  28-MAR-1999  [exchange]
TITLE   :XADM: How to Eliminate DNS's MX records with Multiple Sites
PRODUCT :Microsoft Exchange
PROD/VER:winnt:4.0
OPER/SYS:
KEYWORDS:kbusage

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The information in this article applies to:

 - Microsoft Exchange Server, version 4.0 
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SUMMARY
=======

The MX record on DNS server is used to map a Fully Qualified Domain Name (FQDN)
to a specific Microsoft Exchange Site or Host. This record can be eliminated if
you do not want to use MX records on your DNS server. It can be done by changing
the Microsoft Exchange Site Address to match the FQDN ("A" record) on your DNS
server.

MORE INFORMATION
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You can change this in the Microsoft Exchange Administrator program on the Site
Addressing tab of the Site Addressing Property Page. When you are prompted to
change the Mailbox address, reply yes so that all user SMTP e- mail addresses
match the Site SMTP address. This must be done to all Microsoft Exchange Sites
within the Organization.

The drawback to this type of configuration is that no two SMTP addresses can be
the same within an Organization. Microsoft Exchange will keep this from
happening on new mailbox creations if Directory Replication has happened between
every Site in the Organization, and providing that no two instances of the
Microsoft Exchange Administrator program are creating the same SMTP address at
the same time.

For faster name resolution, it is common to have an MX defined, even if the A
record is the same. This information is from the Microsoft Exchange Concepts and
Planning Guide, page 46.

Additional query words:

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Keywords          : kbusage 
Technology        : kbExchangeSearch kbExchange400 kbZNotKeyword2
Version           : winnt:4.0
Issue type        : kbhowto

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