eg .com returns empty...
-----Original Message-----
From: Paul Gordon
[mailto:paul_gordon@xxxxxxx]
Sent: Wed 29/05/2002 12:28
To: ukha_d@xxxxxxx
Cc:
Subject: [OT]
RE: [ukha_d] How important is static IP? NOW: MX
Records
Mark,
I don't _believe_ this is correct according to
RFC974...
Here's a couple extracts from that
document...
"If the response does not contain an error response, and does
not
contain aliases, its answer section should be a
(possibly
zero
length) list of MX RRs for domain name REMOTE (or
REMOTE's true
domain name if REMOTE was a alias). The
next section describes how
this list is
interpreted"
Thus it is a valid response for a resolver to
return
zero MX records for a
domain in response to a
query..
Additionally...
"It is possible that the list
of
MXs in the response to the query will
be empty. This
is
a special case. If the list is empty, mailers
should
treat it as if it contained one RR, an MX RR with a
preference
value of 0, and a host name of REMOTE. (I.e., REMOTE is its
only
MX). In addition, the mailer should do no
further
processing on the
list, but should attempt to deliver the
message to REMOTE. The idea
here is that if a domain
fails to advertise any information about a
particular name
we
will give it the benefit of the doubt and attempt
delivery."
Thus, according the the RFC, a mailer *should*
attempt
delivery to a domain
that has no MX records using just the domain name,
and
whatever that
resolves to. (So like I said, if the SMTP server is on the
IP
address that
the domain name resolves to, no MX record is
required).
Of course, it may well be that this has subsequently been
superceded by
another RFC which may contradict this, but I'm not aware
of
that being the
case. Additionally I suppose it may well be that certain
mailers don't
implement this feature, but again, I've not come across
any
personally...
One more thing to add I guess is that no-one is
suggesting that this is a
"good thing" to do... I'm just saying that
it's
possible. In a simple
home-user environment, it's possibly best not to
bother with MX records, as
it is quite easy to **ck things up and send
email off to the wrong place!
Paul G.
>From: "Mark
Harrison" <Mark.Harrison@xxxxxxx>
>Reply-To:
ukha_d@xxxxxxx>To:
<ukha_d@xxxxxxx>
>Subject: RE: [ukha_d] How important is
static IP?
>Date: Wed, 29 May 2002 10:18:46 +0100
>
>You
_do_ need an MX record for sending mail to a Domain.
>
>Let me
explain, however, why, AIUI, Paul doesn't.
>
>The Domain in
this
case is HOMEIP.NET - it has an MX record properly
>defined, as
mail.dyndns.org (priority 20) and mail2.dyndns.org
(priority
>50.)
>
>To send email to the SubDomain
paulgordon.homeip.net you first send email
>to the domain
(homeip.net's
mail server). Homeip.net's mail server runs a
>specially modified
routing algorithm to allow it to send mail to wherever
>the SOA is
defined on any of its subdomains.
>
>
>What this means in
practice is that, if you want to host something dynamic,
>then you
don't
need to set up your own MX record - the dynamic domain
>provider will
sort this for you.
>
>If you want to host a real domain, for
example foxybanana.com, you need an
>MX
record.
>
>
>
-----Original Message-----
>
From:
Paul Gordon [mailto:paul_gordon@xxxxxxx]
>
Sent: Tue 28/05/2002 21:49
> To:
ukha_d@xxxxxxx;
wendyjaynegordon@xxxxxxx>
Cc:
> Subject: RE: [ukha_d] How
important is static
IP?
>
>
>
>
Personally, I don't generally find having dynamic IP a problem for
home
>use.
>
> As
previously mentioned, just about the only thing I can't get it to do
is
> to host a provate domain. -
It's usually tied to the namespace that
the
>DDNS
> provider owns,
so
for instance, DynDNS,org have about 20 domain trees
that
> you can choose to be
under,
hence I have Paulgordon.homeip.net, but
I
>can't
> have
gordon-net.co.uk which I also own (but am about to allow to
lapse...)
>
> a couple of
small points to bear in
mind:
>
> 1: - you *CAN*
have
an SMTP feed to a dynamic IP address - I have
one
> working perfectly, - mail
to
paul@xxxxxxx to see it
in
> action...
:-)
>
> 2: - you do *NOT*
_need_ an MX record at all to receive mail, - you
only
> need an MX record if your
SMTP listening server is on a different
IP
>address
> to that which
your DNS "A" record resolves... - Do an NSLOOKUP
on
> paulgordon.homeip.net, you
will
see it resolves to 80.1.127.35 - as
my
>SMTP
> mail server is
listening to port 25 on that IP, I do NOT have (or need)
an
> MX record
configured.
>
>
HTH
>
> Paul
G.
>
>
>
>
>From: "Chris Bond"
<chris@xxxxxxx>
>
>Reply-To:
ukha_d@xxxxxxx> >To:
<ukha_d@xxxxxxx>
>
>Subject: RE: [ukha_d] How important is static
IP?
> >Date: Tue, 28 May 2002
13:27:09 +0100
>
>
> > > It seems a few
of
us are trying to decide which ADLS ISP to go
with
> > > at the moment,
so
I'd like to know just how important those
who've
> > > already taken
the
plunge feel it is to have static
IP?
>
>
> >Well if you want to
use
SMTP mail its very important and it's the
best
> >mail method to use,
don't
need to mess with pop3/imap :)
>
>
> > > Which HA toys
might
need static now or in the near
future?
>
>
> >Lots
:)
>
>
> > > I presume if I
want
to run a mail server I need static for my DNS
MX
> > > record to point
to.
Is this correct, or could you get away
with
> > > something like
dyndns? My guess is that dyndns would sometimes be
out
> > > of date and mail
would get bounced.
>
>
> >I'd stay away from
dyndns
for SMTP mail, there are a few people
that
> >offer backup mx but at
the price you pay u might as well get a
static
>
>ip.
>
>
> >Eclipse charge 26quid
all
inc for Adsl with 5 static ips
:)
>
>http://www.eclipse.net.uk.
>
>
> >Kind
Regards,
> >Chris
Bond
>
>
>
>
>
>
>
_________________________________________________________________
>
MSN Photos is the easiest way to share and print your
photos:
> http://photos.msn.com/support/worldwide.aspx
>
>
>
>
For more information: http://www.automatedhome.co.uk
>
Post message:
ukha_d@xxxxxxx>
Subscribe:
ukha_d-subscribe@xxxxxxx>
Unsubscribe:
ukha_d-unsubscribe@xxxxxxx>
List owner:
ukha_d-owner@xxxxxxx>
>
Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
>
________________________________________________________________________
>
This email has been scanned for all viruses by the MessageLabs
SkyScan
> service. For more
information on a proactive anti-virus service
working
> around the clock,
around
the globe, visit http://www.messagelabs.com
>
________________________________________________________________________
>
>
_________________________________________________________________
Send
and receive Hotmail on your mobile device: http://mobile.msn.com
------------------------
Home |
Main Index |
Thread Index