You're right on both points, I guess I should have said "fully qualified domain name". As I said, I'm no expert.
On the second point, all I know is mail kept getting bounced back until the ISP that was the authority for the
domain name put in an A record for the fully qualified domain name (eg. Y.DOMAIN.COM) for the sending MTA.
"Dave C." wrote:
> On Thu, 7 Mar 2002, Frank S. Bernhardt wrote:
>
> > I'm no expert but I've seen something similar to this at one of my customers. It's the 501 message that looks
> > familiar. In my customer's instance the isp holding their domain name didn't have the fully qualified domain
> > name of the mail server setup as an A record.
> >
> > For example, the customer has 2 servers, X and Y with the domain name of DOMAIN.COM. In the dns hosts record
> > they had X.DOMAIN.COM setup with an A record and a CNAME pointer for Y.
> >
> > Some of the emails they were sending from Y.DOMAIN.COM got bounced with the 501 eeror message. Once the isp
> > setup Y.DOMAIN.COM as an A record, all was well.
>
> For any _domain_ being used as an email address, there really should be
> an _MX_ record, which should point the the _host name_ of the server
> which should receve mail for it.
>
> Eg if <postmaster@???> is desired to be used as an email
> address, there should be:
>
> Y.DOMAIN.COM MX 10 some-host-name-here
>
> People confusing *domains* and *hostnames* is perhaps one of the most
> common confusions regarding DNS. Yes, they look similar. In fact, a
> given string could be either a hostname or a domain, or even both
> (although this generally isn't recommended.)
>
> The A records, while technically legal, are a legacy. Anyone with a clue
> should use MX records.
>
> >
> > Of course also check out Roger Burton West's link to orbz. That's always a good place to get info.
> >
> > Hope this helps.
> >
> > snurt@??? wrote:
> >
> > > Hi All,
> > >
> > > Looks like my adsl proviuder has banned my ip from their smtp server.
> > >
> > > (which i still use now anad again) as I am open relay..
> > >
> > > This was news to me, so i quickly checked...
> > > 501 test: sender address must contain a domain
> > > 250 <test@???> is syntactically correct
> > > 550 relaying to <test@???> prohibited by administrator
> > >
> > > Looks like im not open relay to me..or am I mistaken ?
> > >
> > > THe relaying prohibvited line happened after the rcpt to: but the mail
> > > from: let me put anything in...
> > >
> > > Sigh
> > >
> > > This message sent via webmail
> > >
> > > Oh btw, using exim 3 not 4 :)
> > >
> > > --
> > >
> > > ## List details at http://www.exim.org/mailman/listinfo/exim-users Exim details at http://www.exim.org/ ##
> >
> > --
> >
> > Regards
> >
> > Frank S. Bernhardt
> > b.c.s.i.
> > 14 Halton Court
> > Markham, ON.
> > L3P 6R3
> >
> > 905-471-1691 Voice
> > 905-471-3016 FAX
> >
> > frank@???
> >
> >
> >
> > --
> >
> > ## List details at http://www.exim.org/mailman/listinfo/exim-users Exim details at http://www.exim.org/ ##
> >
> >
>
> --
--
Regards
Frank S. Bernhardt
b.c.s.i.
14 Halton Court
Markham, ON.
L3P 6R3
905-471-1691 Voice
905-471-3016 FAX
frank@???
