March 26, 2008
10:58 a.m.
--On 25 March 2008 08:13:49 +0100 Lars Magne Ingebrigtsen <larsi@gnus.org> wrote:
These days, secondary MXs usually do SMTP callouts to verify whether email addresses are valid on the primary mail server. It does, however, make the concept of a "secondary MX" less useful than it used to be.
Yes. The architecture sucks. We abandoned it about 10 years ago for an LDAP user database that all our SMTP hosts (we have four peers) can access. The database has four mirrors. If the database isn't available (I can't remember the last occasion), we use a 4xx error and ask the sender to hang on to the mail for us.
-- Ian Eiloart IT Services, University of Sussex x3148