[Gllug] speaking of DNS server setups...

[Benedikt Heinen]

>> Is it possible, with bind9 or another name server, to specify part of a
>> domain name as a wildcard?
>>
>> e.g.  I would like to define the same setup for all *.foo.net hosts, so
>> that www.a.foo.net, www.b.foo.net, ... www.zyx-cba.foo.net all point to
>> the same host?
> Yes, it's simple to do.

Is it also possible for SUBDOMAINS?

I take it, if I can specify

 	*	IN	A	192.168.0.1

I could just as well specify

 	*	IN	NS	192.168.0.1

but, what about the zone file / named.conf?

Within the zone file, can I write

 	$ORIGIN *.foo.net.

with the * coming in as planned?  (Similarly, in named.conf, can I specify

 	zone "*.foo.net" { [...] }

)?



>> Second, and now it gets more interesting, can I specify exceptions?
> Yes. The wildcard is used only where there is no explicit record.

Can I specify a "non-record", or do I have to create an illegal one?

(remember the example, I want the exception to REMOVE a name)?

OK, I might just

 	dontwantitanymore	IN	NS	127.0.0.1

or - if I wanted to make sure the spammer wastes time on name lookups, 
specify

 	dontwantitanymore	IN	NS	192.168.42.191

[or other non-routed address; 127.0.0.1 will fail too fast...]


>>  [ * MX records ]
> I would avoid this though as it makes life really easy for spammers and
> really hard for you.

Actually, my idea is to use it against spammers...

Right now, I am using a handful of subdomains to handle specific stuff, 
and create new addresses within those domains as I see fit.

The problem sets in, when I want to remove a single address -- there are 
still loads of attempts to send an email to that address. If I had a 
sub-domain per recipient, I could turn off individual subdomains if I got 
spammed on that one - effectively reducing traffic, as there will be DNS 
traffic only...

Also, if I dynamically created subdomains for this purpose, I could still 
make it very tough for the sender, if I still only define ONE specific 
user in the domain and discard everything else...


> It's trivially easy to add an record to a database table to activate a
> subdomain or other recipient "site" in postfix.

Yes, that's what I'm aiming for, making it as easy as possible to 
extend...






   Benedikt

 	INFLUENCE, n.  In politics, a visionary _quo_ given in exchange
 	  for a substantial _quid_.
 			(Ambrose Bierce, The Devil's Dictionary)
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