Re: mail confusion

[Derek Martin]

On Sat, Nov 05, 2005 at 11:12:45PM +1030, Tim wrote:
>  > For local networks, DNS is utterly and completely unnecessary,
> and so
>  > too are FQDNs.
>  
>  I'm not so sure that I'd go along with that.  Try booting up a graphical
>  Linux client station without a hostname associated with a local IP
>  address, and you're in for a bit of grief.  It doesn't like the idea of
>  you being user at 127.0.0.1 or unresolveable hostname. 
You have made a fatal error here...  You are equating hostnames with
fully qualified domain names.  They are not the same.  It is perfectly
acceptable to have a hostname which is not a fully qualified domain
name, and X will not have any problems dealing with that, so long as
there is some method of resolving it to an IP address on your host (of
which there are many other than DNS: host files, NIS, NIS+, LDAP,
netbios, Active Directory, etc., etc.).  DNS and BIND are far from the
only name-resoultion game in town...  But it is the only one that uses
FQDNs.

DNS works fantastically well for the Internet, where as the other
schemes generally could not.  But, they are perfectly valid and useful
for local networks.

>  > a bad idea.  It's a lot of needless configuration, and if
> you
>  > should need to connect those systems to the net later, you'll just
>  > need to do it all over again.  Better to have some forsight and
>  > get a real domain.
>  
>  Now, I would agree with that.  But a few years ago, here, registering a
>  domain name was an expensive process.  It still can be (we'd be paying
>  $100 for what other countries charge $1). 
Then register it in a different country!  ;-)  I know people from the
US who've registered domains in France, and other places...  We live
in a global community now.  You are not bound by your country's
borders any longer!  ...and there was much rejoicing.  :)

>  > Well, at the risk of sounding like a broken record, to sum it
> all up:
>  > If you are not participating in the public Internet, there simply is
>  > NO NEED to have one, and I can't even think of a useful purpose that
>  > it serves to have a fake one, if your network consists of only a
>  > handful of hosts.
>  
>  Testing SSL communications, in-house.  They need domain names for the
>  certificates.  :-p 
No, they need X.509 Distinguished Names.  That's also not the same as
a FQDN, even if most every site uses their FQDN as their DN.
Internally, your DN need only match your internal host resolution
scheme, which could be X.509 itself (which generally has been replaced
by LDAP), and need not make use of DNS whatsoever.  Sorry Charlie, but
nice try.  ;-)

>  > So if you are avoiding registering a legitimate one for some
> valid
>  > reason, you may as well not use one at all, and stick to hostnames
>  > only.  If you ARE participating in the public Internet, you should
>  > have a LEGITIMATE domain.  None of this necessitates a FQDN
>  > for 127.0.0.1, and nothing ever will, other than broken software.
>  
>  I'm not sure why 127.0.0.1 comes into the argument.  I was talking about
>  local networks, not just the one machine. 
Because you were responding to my original post, where I said that I
thought the whole idea of localhost.localdomain (vs. simply localhost)
is brain-damaged.  That's what started this thread.

-- 
Derek D. Martin
http://www.pizzashack.org/
GPG Key ID: 0x81CFE75D