DOCUMENT:Q266250  24-NOV-2000  [exchange]
TITLE   :XFOR: Internet Mail Service on Cluster Uses Node IP Address
PRODUCT :Microsoft Exchange
PROD/VER::5.5,5.5 SP1,5.5 SP2,5.5 SP3
OPER/SYS:
KEYWORDS:exc55 exc55sp1 exc55sp2 exc55sp3

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The information in this article applies to:

 - Microsoft Exchange Server, versions 5.5, 5.5 SP1, 5.5 SP2, 5.5 SP3, used with:
    - the operating system: Microsoft Windows 2000 
    - the operating system: Microsoft Windows NT 
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SUMMARY
=======

When the Exchange Server 5.5 Internet Mail Service is installed and configured
on either a Microsoft Windows 2000 or a Microsoft Windows NT 4.0 cluster,
Internet Mail Service uses the physical node Internet Protocol (IP) address
instead of the Exchange-based server's virtual IP address.

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

You can use protocol logging and a network trace to determine what occurs when a
node makes an outbound connection. The protocol log reports that the connection
is coming from the cluster IP, but the network trace reports that the connection
is using the IP address that is bound to the network adaptor on the node. This
behavior can be an issue if a firewall has been implemented. If all IP addresses
except for the cluster IP are blocked, traffic from the nodes is stopped, and
the Exchange-based server is not able to send and receive mail.

The Exchange 5.5 Internet Mail Service does not use cluster APIs. Socket programs
can only use the virtual address when the socket programs are rewritten with
cluster APIs, which are able to reference the virtual IP addresses that can be
used.

This behavior does not occur in Exchange 2000 Server because the architecture has
been modified.

For additional information, refer to the Cluster.doc file in the
Docs\Word_docs\Clustering folder that is located on the Microsoft Exchange
Server 5.5 CD-ROM.

Additional query words: cluster IMS node virtual

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Keywords          : exc55 exc55sp1 exc55sp2 exc55sp3 
Component         : IMS ServerClustering
Technology        : kbExchangeSearch kbZNotKeyword2
Version           : :5.5,5.5 SP1,5.5 SP2,5.5 SP3
Hardware          : ALPHA x86
Issue type        : kbinfo

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