On Wed, 28 Apr 2004 22:46:54 +0100 Jeremy Harris <jgh@???> wrote:
> Tom Playford wrote:
> > 2004-04-28 21:53:09 1BIQbt-0000qF-00 ==
> > help@??? T=remote_smtp defer
> > (0): SMTP error from remote mailer after RCPT
> > TO:<help@???>: host
> > oxmail.ox.ac.uk [163.1.2.161]: 451-Invalid HELO (**my-server-name**)
> > used by **my-server-ip**. See
> > RFC2821 S4.1.1.1 for syntax\n451-of the HELO command. This is a
> > temporary error. You may try again
> > after\n451 this server (**my-server-ip**) has been fixed.
> *my-server-name* either includes an underbar, or fails to
> includes any dots? Your HELO name is supposed to be
> an FQDN.
to be pedantic, it can also be an ip address inside of square
brackets, e.g.
HELO [192.0.2.5]
i generally reject bad syntax in HELO myself (except for
those $%$@#!@$ _ characters beloved of M$ administrators).
rejecting ip addresses not inside [] kills a lot of abusive email
with few if any false positives, at least that i can see. likewise,
better than 99% of hosts doing something like
HELO FXEKDF
are hosts you don't really want to accept email from; very
few false positives there.
richard
--
Richard Welty rwelty@???
Averill Park Networking 518-573-7592
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