[Lias] Re: postfix etc

[Andrew Dorrell <andrew.dorrell@cisra.canon.com.au>]

Parkes High School wrote:
> Hi Andrew
>
> One thing that puzzles me is the difference between 127.0.0.1 and the IP
> one gives a machine...say 10.12.217.88
well... you don't actually give the address to the machine, you give it 
to the interface.  The address 127.0.0.1 refers what is called the 
"local loopback" interface.  Whenever you want to connect specifically 
to the machine you are sitting at you can use it, and services that you 
do not want used by others can be configured to only accept connections 
from this address.  This is how your postfix server was configured out 
of the box.

Now, to talk TCP/IP on your network card you need to give that interface 
an address also - this is the 10.12.217.88 one.  In fact you can add any 
number of "alias" addresses for this interface also... and I recommend 
doing that (see http://www.tldp.org/LDP/nag2/index.html if you have the 
time...).  I assume Mandrake will give you a configuration tool for 
doing this... if you can't find one just add a few lines like the 
following in your /etc/rc.local:

/sbin/ifconfig eth0:0  <first extra address>
/sbin/ifconfig eth0:1  <second extra address>
...

In particular, DET asigns addresses in its DNS for

proxy.parkes-h.schools.nsw.edu.au
mail.parkes-h.schools.nsw.edu.au
web1.parkes-h.schools.nsw.edu.au
etc

to get the exact addresses, assuming you have DNS configured, just type 
for example

host proxy.parkes-h.schools.nsw.edu.au

If you are running this machine as a proxy and mail server then add 
aliases for these addresses _and_ the corresponding entries in your 
/etc/hosts



But now to get to your specific problems:


parkes-h.schools.nsw.edu.au should be your domain name and not your 
hostname which should be something like tux.parkes-h.schools.nsw.edu.au! 
 Make a point of fixing this or you will have problems.  A good 
/etc/hosts entry might be:


10.12.217.88 tux.parkes-h.schools.nsw.edu.au   tux


The change you made to the postfix allows _all_ computers to access and 
use your SMTP service.  This is why it was required for client PC's on 
your network to access the postfix server.

You should make the following change to postfix's main.cf also:

   mydestination = $myhostname, localhost.$mydomain, $mydomain

which will inform the server that it is the termination point for mail 
addressed user@parkes-h.schools.nsw.edu.au

For forwarding to the outside world add:

   relayhost = [smtp.schools.nsw.edu.au]


Then you should be cooking with gas ;-)


Sorry to hit you with that much at once... do the last things first and 
worry about aliases later... that just makes things more integrated and 
nicer

> I just set up a Red Hat 7.3 box and gave it the hostname you suggested -
> parkes-h.schools.nsw.edu.au
> I installed Postfix and Cucipop.
> To get postfix to work I had to make an entry in the hosts file -
> 10.12.217.88 parkes-h.schools.nsw.edu au
> There was only 127.0.0.1 localhost there.
>
> Also had to go in and edit Postfix's main.cf file to get inet_interfaces
> from localhost to  all .
> Have no idea if that last was a good idea.
> Next thing is to try to get internal mail forwarded on to the outer
> world.
>
> Peter
>
>
>
>
>
> -----Original Message-----
> From: Andrew Dorrell [mailto:andrew.dorrell@cisra.canon.com.au] 
> Sent: Thursday, 31 October 2002 7:47 AM
> To: Parkes High School
> Subject: Re: postfix etc
>
> Parkes High School wrote:
>
> > *Hello again Andrew*
> >
> > * *
> >
> > *I just installed a telnet server on the Mandrake 9.0 box and can now 
> > telnet into it from another machine on the network - to both port 23
> and 
> > port 25 - but still cannot send a test email from the workstation to
> the 
> > smtp server - Postfix.  So it seems like a Postfix configuration
> problem 
> > perhaps?*
>
> I see you have now received some other answers that are knowledgable 
> about postfix - good :-)
>
> The reason for trying to telnet to port 25 is that this is the port your
>
> SMTP server listens on.  Being able to telnet to it just shows that its 
> there and working - helps you narrow down where to look.  But you have 
> that now with the postfix forwarding configuration fix.
>
> Hope it goes well.
>
>
> > *The pop server cucipop does not give an error*
> >
> > * *
> >
> > *Peter*

--
Andrew Dorrell PhD.        Senior Research Engineer
Canon Information Systems Research Australia     Phone: 61 2 9805 2224
1 Thomas Holt Drive,  North Ryde,  NSW 2113.     Fax:   61 2 9805 2865