RE: [cobalt-users] DNS HOWTO - MX Record www.domain.com - Why?

[flash22@xxxxxxx]

On Mon, 27 Aug 2001, Brandon Trussell wrote:

> >But why the redundancy? There's nothing funny or weird about setting MX
> >to www.mydomain.com - you are getting too fixated on the "www" part of
> >the domain name.
> >
> >It's the *name of the virtual site* that matters and it just happens to
> >be www.mydomain.com
> 
> Ahhhhhhh. I think I get it now. The above statement applies when I set up a 
> new site with a "fully qualified domain name" (per the Cobalt manual) as 
> www.mydomain.com. But I'm missing one critical step in here somewhere....
> 
> if I *never* set an MX record or A record for mail.mydomain.com, how the 
> heck does it work when a user sets their mail client to send/receive from 
> mail.mydomain.com? My guess is it wouldn't, and they'd have to just set 
> their mail server as mydomain.com (no hostname). Is this right?

Correct, because the client will have no way to resolve mail.mydomain.com
(Tho most clients blithly allow bogus domain names as return addresses ;)

> 
> And one of you guys please check out my previous post,
> " [cobalt-users] DNS on RaQ 4i: primary name server defaults to host name? 
> (long)"
> no one has replied yet...

Cause it's not gonna be a clean answer ;)

Ok, assuming the 4i has the same dns scripts as the 3's, for that part
anyhow, it will insist on adding NS records for it's primary IP address,
and it's hostname will be the default name for this IP in the NS records,
however, nothing whatsoever requires you to point an authorative
nameserver at it , eg when you register nameservers you can specify some
other IP on the machine , the extra useless NS record won't mean anything
to anyone , as it's not going to be asked for anyhow. 

However if you use the same IP and also add NS records to that IP address
to use it as a nameserver, then you will be replying with an extra piece
of information that is , unfortunatly wrong, tho not badly, and most
clients will ignore it....

You can identify raq's whis way when looking up domain names sometimes btw
-/

Is this clear as mud?

Now JL will probably yell at me for saying a small dns error is not
serious -/

gsh