20 domains on 1 server

[Barry Margolin]

In article <959726546.4832.0.pluto.d4ee69f1 at news.demon.nl>,
Oldserver <marc at oldserver.demon.nl> wrote:
>Very basic questions, which I cannot find an answer to in the O'Reilly
>Book.
>
>I am setting up DNS for some 20 domains on one server, which is going ot
>do everything: dns, mail and web.
>
>1. I see others do this as follows (for each domain):
>
>@     IN A     10.10.10.10
>mail   IN A     10.10.10.10
>www IN A     10.10.10.10
>
>Now if my server is marc.venster.net, it could also be done thus (except
>in the zone for venster.net of course):
>
>@    IN CNAME marc.venster.net.

This is not valid, because it violates the rule against "CNAME and other
data".  Either a name is an alias or it has its own records, it can't be
both.  Since @ has to have SOA and NS records, it can't be an alias.

>mail  IN A       marc.venster.net.

I think you meant to make this a CNAME, not an A record.

>www IN CNAME marc.venster.net.
>
>Why not? Extra lookups? It looks "cleaner", as otherwise this machine
>would have a hundred hostnames...

You can use CNAMEs for everything but the @ record, so you could do:

@ IN A 10.10.10.10
mail IN CNAME @
www  IN CNAME @

>2. All the zone files (or nearly all) will be identical. What do I do to
>keep it "clean"? Copy the file 20 times to the different names or link
>them with ln -s? Last option would be easiest in case a change is needed
>some time. I understand the named.conf want them all listed. Or can I tell
>it that e.g. db.basic is the zone file for all domains, like this:

Yes, you can use the same file for all of them.  Just make sure you use
relative domain names throughout, as in the above example.

>
>zone "venster.net" in {
>            type master;
>            file "db.basic";
>};
>
>zone "venster.org" in {
>            type master;
>            file "db.basic";
>};
>
>zone "superputer.com" in {
>            type "master";
>            file "db.basic";
>};
>
>Thanks!
>
>Marc Schneiders
>
>
>
>
>


-- 
Barry Margolin, barmar at genuity.net
Genuity, Burlington, MA
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