Re: Second E-mail server

[Adam Tauno Williams <awilliam@xxxxxxxxxxxxx>]

>The plan I had is only put a A record in DNS but not MX and PTR record.  I think if
>I put a MX record, it will become a secondary mail server on the network.  Unless
>there is a way to put two primary mail servers on the network. Also I will not
>change the serial No. on DNS to update the upstream  DNS.  In that way, if something
>going wrong, the DNS won't get poisoned.   Do you think that will work?

Sure.  You should put in an MX record for "testmail.foo.com" to get the mail sent to "testmail.foo.com",  it won't affect any mail except that addressed to "@testmail.foo.com".  If you don't other mail exchangers may never send it the mail (depends how they are configured).  Your right though, you can't put a second MX for just "foo.com" without screwing things up.