using DNS Hinfo to forward emails per email account

[Jim Reid]

>>>>> "Roy" == Roy  <Roy.Riazati at piamerch.com> writes:

    Roy> I am going to move my email accounts on my mail server to
    Roy> another server in different domain in phases.  That is,
    Roy> userA at domain1.com is going to be removed from this server and
    Roy> moved to a server in domainB.com.  I want the DNS forward any
    Roy> messages that is addressed to userA at domain1.com to a
    Roy> host(mail server) in domainB.com.

This is not a DNS issue. It's a mail routing issue. Name servers don't
(can't) forward mail.

    Roy> I have seen AT&T doing this by using the HINFO record long
    Roy> time ago and I need any help about how to use either HINFO
    Roy> record to do this task, or any other method that you
    Roy> personally have experienced with.

The HINFO record is obsolete. I'm mystified how anyone could use this
to route mail. All HINFO records contained were two strings: one for
the hardware platform and one for the OS version.

What you need to do is play with the mail software on the mailhub that
gets all the mail sent to domain1.com. [In DNS terms there will be an
MX record for domain1.com which points at some SMTP server.] When mail
arrives as that mail server it has three choices. It could bounce the
mail "unknown user"; it could deliver it to a local mailbox; or it
could forward the message to some other mail system. For the last two
options there is usually an alias table or something like that which
determines what happens. So when mail for user1 at domain1.com arrives,
the mail system looks up user1 in that alias table and puts the mail
into user1's mailbox. Mail for user2 at domain1.com is to be sent to
user3 at domainB.com, so your mail system munges the headers and then
forwards the mail to the mail server for domainB.com.

If you need more information, go ask the people in comp.lang.sendmail.