naming my intranet

I've been looking for answers to this for a while but haven't seen
anything that matches my situation.

I have a domain name with website and mail server hosted remotely
(www.example.com and mail.example.com).

I have a small network of PCs and Macs connected to the internet
through a Linux server over a dynamically addressed ADSL connection.
The linux box is running dhcp, named, iptables and everything is
working fine. I have an internal web server runing for local testing
purposes.

I have named all the computers internally as myhostname.example.local

What I would like to do is maintain the web site and mail server on the
remote host and collect mail using Fetchmail and send mail directly
from the linux gateway using Postfix. I can't seem to get Postfix to
work using the domain names example.local without fiddling with the
settings. It works when running on another server within the intranet
but not on the gateway. I can setup a mail server on the intranet but
my real need is to be able to send locally instead of having to rely on
a remote mail server.

My questions:

What is the best practice for naming machines in the intranet?

Can I rename my server to gateway.example.com?

Can I name the intranet machines myhostname.example.com?

Do I need to make any changes to my DNS records at the remote host if I
do this?

On 16 Mar 2006 22:13:17 -0800, (E-Mail Removed) wrote:

>I've been looking for answers to this for a while but haven't seen
>anything that matches my situation.
>
>I have a domain name with website and mail server hosted remotely
>(www.example.com and mail.example.com).

Hope not, they're blackhole destinations

>I have named all the computers internally as myhostname.example.local
No good at all, not gonna fly


>What is the best practice for naming machines in the intranet?

Honesty, honestly

>Can I rename my server to gateway.example.com?
Not a good idea, the name is taken.

>Can I name the intranet machines myhostname.example.com?
Ditto

>Do I need to make any changes to my DNS records at the remote host if I
>do this?

Nothing good will come us this, avoid blackholes.

Grant.
--
Memory fault -- brain fried

OK, let's try again. At the top of my message, I meant to say: I'm
using example.com as an example. I do actually have a real domain name
registered. Several, in fact.

(E-Mail Removed) writes:

> What is the best practice for naming machines in the intranet?

I don't know what's actually best. Something that has worked quite
well for me is to give them all a subdomain name (in my case,
wb.comcast.net -- all the permanent machines around the house are
named after after Warner Brothers cartoon characters). All the
machines at home are members of this subdomain.

> Can I rename my server to gateway.example.com?

This is your server at home? I named mine pinky.wb.comcast.net.
Works fine.

> Can I name the intranet machines myhostname.example.com?

snowball.wb.comcast.net
babs.wb.comcast.net
noodlenoggin.wb.comcast.net
etc.

> Do I need to make any changes to my DNS records at the remote host if I
> do this?

No. I run a bind9 server (and a dhcpd server) on snowball. From
inside the house, everything is in wb..., from outside it's all
invisible.
--
Joseph J. Pfeiffer, Jr., Ph.D. Phone -- (505) 646-1605
Department of Computer Science FAX -- (505) 646-1002
New Mexico State University http://www.cs.nmsu.edu/~pfeiffer

On 16 Mar 2006 22:13:17 -0800, (E-Mail Removed) wrote:
> I've been looking for answers to this for a while but haven't seen
> anything that matches my situation.
>
> I have a domain name with website and mail server hosted remotely
> (www.example.com and mail.example.com).
>
> I have a small network of PCs and Macs connected to the internet
> through a Linux server over a dynamically addressed ADSL connection.
> The linux box is running dhcp, named, iptables and everything is
> working fine. I have an internal web server runing for local testing
> purposes.
>
> I have named all the computers internally as myhostname.example.local
>
> What I would like to do is maintain the web site and mail server on the
> remote host and collect mail using Fetchmail and send mail directly
> from the linux gateway using Postfix. I can't seem to get Postfix to
> work using the domain names example.local without fiddling with the
> settings.

Of course, your gateway relayhost would be the remote MTA
and gateway will be releayhost for all the LAN systems.

You can use canonical, canonical_sender, canonical_recipent, virutal,
to munge headers for routing to your local LAN.

> It works when running on another server within the intranet
> but not on the gateway. I can setup a mail server on the intranet but
> my real need is to be able to send locally instead of having to rely on
> a remote mail server.
>
> My questions:
>
> What is the best practice for naming machines in the intranet?

The domain will have to be registered and in a DNS server and domain
not used by anyone else on the net. Node names are your choice.

For some background info
http://www.faqs.org/rfcs/rfc883.html
http://www.faqs.org/rfcs/rfc1035.html

> Can I rename my server to gateway.example.com?

Assuming you are talking your nangura.net node, mine is fw.home.invalid
But since it is a comast node, it's registered name is
c-24-1-202-185.hsd1.tx.comcast.net

> Can I name the intranet machines myhostname.example.com?

To route to them from somewhere else, an internet dns server would have
to know about them.

> Do I need to make any changes to my DNS records at the remote host if I
> do this?

It is going to take a dns server somewhere, to resolve name to ip addy.

For postfix routing http://www.postfix.org/

Thanks for the information and suggestions, I am starting to get a
clearer idea of what I need to do to achieve the following:

web server located remotely using my registered domain name - OK
mail server located remotely using my registered domain name - OK

i do not need to have anything on my intranet accessible from outside -
OK

I want to be able to send mail directly from my gateway computer, which
has a dynamic address but does not need to be contacted from outside
the intranet. This is mostly working. I prefer to send directly rather
than use my external mail server as a relay host.

I can retrieve mail from my external mail server using Fetchmail and
make it available via pop on the intranet from the gateway computer.

I have added a text record to my external MX records which covers the
range of addresses allocated by my ISP. This seems to work with mail
servers such as AOL which do reverse DNS lookup.

So far, so good, and without having to get into running an NIS server
which is something else I don't yet know how to set up correctly. It
seems that the Macs prefer this setup rather than relying on a hosts
file so I will continue with the setup. I think its working but I'm
running on luck rather than judgement here.

I seem to have everything working apart from one important feature:

Normally I want internal mail - mail sent within the domain - to stay
local instead of having to go out to the mail server and then be
retrieved. This part is OK, but I want the flexibility of being able to
switch this off for some users so they can retrieve their mail direct
from the external mail server when on the road. So far, all I can do is
alias them in Postfix to send their mail to a different external mail
domain, like yahoo or gmail.

It works, but its not quite perfect. Is this something I can do in
Postfix or do I have to continue with the internal domain setup?

Thanks for the previous help and advice and hoping someone can give me
a few more clues