Hi

Stephane Bortzmeyer wrote:
> On Thu, Sep 16, 2004 at 08:23:53AM +0200,
> Arun Dev wrote
> ...
>
>>I know this is a really newbie question.

>
>
> Moreover, this is a question that could be solved by setting up a
> dummy name server at home and testing with BIND. Any second-hand PC
> with a free Unix is more than enough for learning DNS by practice.


Still many thanks for your detailed answer!

It is all bewildering at the beginning. I will make it a point to
"play" with a test installation. Running bind on an isolated machine,
and querying nslookup with server as localhost, would that be
sufficient?

> Moreover, you gave no indication on the name servers. I assume they
> were:
>
> ns1.schoolx.yz with the IP address X.Y.Z.T (the primary)
> ns1.isp.net with the IP address O.P.Q.R (a secondary)


The school does _not_ have its own nameservers (that's the
whole problem). So the authoritative nameservers will look like

ns1.isp.net
ns2.isp.net

which are known to us. We are going to tell their administrators
to add the few lines required by us.

> Zone file of schoolx.yz :
>
> $TTL 86400
> @ IN SOA ns1.schoolx.yz. hostmaster.schoolx.yz. (
> 2004091701 ;serial
> 21600 ;refresh
> 3600 ;retry
> 3600000 ;expire
> 86400 ); minimum
> IN TXT "Domain configured without any warranty"
> IN NS ns1
> IN NS ns1.isp.net.
> IN TXT "v=spf1 a:mail.schoolx.yz -all"
> IN MX 10 iron
>
> ns1 IN A X.Y.Z.T
> iron IN A A.B.C.D
> www IN CNAME iron
> mail IN CNAME iron


The last 3 lines are the ones for forward lookup.

> Zone file of c.b.a.in-addr.arpa (you have the delegation of the /24?) :
>
> $TTL 86400
> @ IN SOA ns1.schoolx.yz. hostmaster.schoolx.yz. (
> 2004091701 ;serial
> 21600 ;refresh
> 3600 ;retry
> 3600000 ;expire
> 86400 ); minimum
> IN TXT "Domain configured without any warranty"
>
> d IN PTR iron.schoolx.yz.


Again the last line is the critical one.

Why you all omit the first three numbers of the IP-address
(d instead of a.b.c.d)?

>> - the outgoing mail should carry from addresses in the form
>> user@schoolx.yz

>
> This is a mail issue , off-topic for this list. What is the mail
> server software?


True. That I can test separately.

>> - our provider's mail server should store incoming mail in case
>> the machine or the SMTP daemon is down

>
>
> Bad idea, IMHO, so I did not implement it. (Unless you have a very
> good working relationship with the ISP.)
>

I was thinking of the MX records. Usually one gives top priority
to the own server and backup servers get less priority.

bye
Arun