Re: [gentoo-user] A DNS question.

[Michal 'vorner' Vaner]

On Sat, Mar 03, 2007 at 03:21:52PM -0600, Dan Farrell wrote:
> On Sat, 3 Mar 2007 22:04:59 +0100
> "Michal 'vorner' Vaner" <vorner@×××.cz> wrote:
>
> > Hello,
> >
> > On Sat, Mar 03, 2007 at 11:17:52AM -0800, Bob Young wrote:
> > > Obviously on a given system each NIC is usually connected to a
> > > different domain, my question is, whether or not it
> > > is /legal/possible/okay to use different *hostnames* on different
> > > NICs?
> >
> > AFAIK, you can have multiple names for one IP and multiple IPs for one
> > name (there are more ways to do that). So, I see no reason why anyone
> > would ever forgive you to have different name for each of IP addresses
> > your computer has. The other question is if you really want to do
> > that, because there might be applications not expecting your computer
> > is "schizophrenic" in such way and go nutty.
> >
> > With regards
> >
> on the contrary, there are good reasons to have more than one name for
> a single computer.  For example, say I have a server 'zeus.mydomain'
> that also does mail.  If I name the mailserver 'mail.mydomain' then I
> can CNAME that to zeus.mydomain via DNS, or I can just set
> mail.mydomain to the ip address of the second interface.  Result - I
> can redirect my mail to mail.mydomain and it can go to whatever
> computer I desire, whether or not it has different names.  'zeus' is
> still listening under that name for other requests.  If i use 'zeus'
> for heavy filesharing, I can still get good access over a non-saturated
> ethernet device on 'mail'.

Well, this is something else - the computer knows itself as zeus and has
"nicknames". However, if I got what the question was about - to be name1
for one card and name2 for the second - and do not appear as name2 on
the first at all.

IMO machine should have the same "base" name to any domain it shows in -
the one that it shows in bash command prompt. Then you can have
additional names for the services and they can differ.

But the name showed on the bash should probable be reachable (if
possible) from any network it appears on. The situation shown here is
probably odd (the names here are the only ones there, no additional ones
or base ones).

[ X ] C1 ---- C2 [ X ] C1 ---- C2 [ X ].

The [ X ] is a machine, ---- is a network and those C? are names of the
machine on the net. Now, ping C1 on the middle machine. Should it ping
itself on the right interface or look for the left computer? You should
at last have something like:

[ Name1 ] C1 ---- C2 [ Name2 ] C1 ---- C2 [ Name3 ]

(even if Name2 could not be resolved by the DNS on the right network for
example).

And you can "nickname" Name2 as mail or ntp if it suits you.

I hope I made myself clear and I apologize for the previous
misunderstanding.

Have a nice day

-- 
Anyone who goes to a psychiatrist ought to have his head examined.
		-- Samuel Goldwyn

Michal 'vorner' Vaner