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Matt Kolb writes:

> We are in the process of white listing all departmental e-mail
> servers.  If you are responsible for a legitimate departmental e-mail
> server, please e-mail me with the server name, and your contact
> information so I can white list you.

I have passed on a list of all mail server on campus, as identified by
searching the DNS data for all MX records under "msu.edu" and any
subdomains under "msu.edu".  I have included those listed on DNS servers
under departmental control, where I provide secondary name service on
the central name servers.

If you were not aware of this, it is a good practice to place an MX record
in the DNS data for all mail servers and other computer systems which handle
SMTP mail.  MX records are required in cases where the mail domain is
different from the mail server name, e.g.

  dept.msu.edu     MX  10   mailserver.dept.msu.edu

so we know all of those mail servers are listed.

When the mail domain is identical to the host name, mail can be delivered
with only an A record (name to IP mapping), but it's best to also include
an MX record.

For example, you might have a departmental mail server with the entries:

  dept.msu.edu     A    35.8.22.33

You should also include:

  dept.msu.edu    MX  0   dept.msu.edu

For those of you who use the centrally-administered name service, you should
check the listings for your department at:

  http://www.dns.acns.msu.edu/hostfile/hosts/

Look for the appropriate "MX" records for your mail servers.  MX records
are also generated for host entries in these files, if the tag "{mx}" is
present in the "comment" field of the host entries.

To repeat the above examples, the DNS records would be represented in the
central DNS host files as follows:

  MX: dept.msu.edu: 1: mailserver.dept.msu.edu

or

  35.8.22.33  dept.msu.edu    # {mx}

If you need additional MX records on the central name servers, send a message
to "[log in to unmask]" with the appropriate updates.  If you are not familiar
with requesting DNS updates, take a look at:

  http://network.msu.edu/public/ipadmin.html

Doug


Doug Nelson, Network Manager             |  [log in to unmask]
Academic Computing and Network Services  |  Ph: (517) 353-2980
Michigan State University                |  http://www.msu.edu/~nelson/