Re: [cobalt-users] MX record question / Raq4i

["Ben Liddicott" <ben.liddicott@xxxxxxxxxxxxxxxxxx>]

RFC1033 isn't an authority document; as it says at the top, it is a set of guidelines.
RFC1480 "does not specify an internet standard".
RFC974 "presents a description of how mail systems on the Internet are expected to route messages", which bears no relation to how
they actually do so. It thinks for example that hosts use WKS records to show that they accept mail. Does any MTA check WKS records?

Are there any actual standards or standard documents? It would be nice to know.

Cheers,
Ben Liddicott
----- Original Message -----
From: "Jeff Lasman" <jblists@xxxxxxxxxxxxx>


> flash22@xxxxxxx wrote:
> > The authority document is RFC1033
> >
> >   "MX records specify where mail for a domain name should be delivered."
> >
> > Note that it says 'domain name' , not just 'domain', The RFC's tend to
> > have very precise language, most of the time, usually, generally ;)
> >
> > Other obscure trivia, for folks using CNAMES for web aliases
> >
> > RFC974 requires resoloution of CNAMES *before* MX lookups (client)
> >
> > Apparently, this was worded too obscurely, as
> > RFC1480 went to the trouble to specificly prohibit MX -> CNAME-RR
> >
> >   "It is not appropriate to ask to MX "your-host" to "path-host" (this
> >    is sometimes called double MXing).  The host on the right hand side
> >    of an MX entry must be a host on the Internet with an IP address"
>
> Thanks for taking the trouble to document this; I didn't want to take
> the time to look it up <smile>.
>
> Jeff
> --
> Jeff Lasman <jblists@xxxxxxxxxxxxx>
> Linux and Cobalt/Sun/RaQ Consulting