On Sunday 11 March 2007 12:13, Uri Even-Chen wrote:

> Of course I want to learn, but I don't understand what's wrong with
> the current configuration.  And also, many technical people forget
> that hardware costs money.  2 servers would cost me double; 3 servers
> would cost me 3 times etc.  I'm not Google, I don't have millions of
> servers.  If I can save money by putting everything on one single
> server, and if it works - then what's wrong with it?  I don't see any
> problem with solving domain names recursively while being open to
> queries from the entire world.

And of course no one said that you need to buy more hardware, just
run two BIND servers on the same machine, each bound to its own
IP address...

> Of course, if my service was abused and things were not working,
> that's a different issue.  But since it works, I don't see any reason
> to change the current configuration.  I don't agree with your opinion
> that my current configuration is wrong.

How would you even know if your service is abused ?  Are you waiting
for it to be abused ?  What kind of technical (or management) decision
is this ?

But since you think it's my opinion, let me quote a few other opinions:


http://www.zytrax.com/books/dns/ch4/
...
Note: Running any DNS server that does not require to support recursive 
queries for external users (an Open DNS) is a bad idea. While it may look 
like a friendly and neighbourly thing to do it carries with it a possible 
threat 
from DoS attacks and an increased risk of cache poisoning. The various 
configurations have been modified to reflect this.
...

http://articles.techrepublic.com.com/5100-1035_11-5860968.html
http://www.sprintlink.net/faq/dns.html

http://net.berkeley.edu/DNS/recursion-detail.shtml
...
It is possible to have both authoritative and caching functions running 
on the same DNS server, and this was typical in the early days of the 
DNS.  More recently it has become a best practice to separate these 
functions, and IST did this a few years ago.  More information on our 
DNS servers can be found here (http://net.berkeley.edu/DNS/campus.shtml)
...

http://cr.yp.to/djbdns/separation.html
...
The importance of separating DNS caches from DNS servers

DNS caches should always have separate IP addresses from DNS servers. 
In other words, the IP addresses listed in /etc/resolv.conf should never match 
any IP addresses listed in NS records.
This separation is widely recognized as the right way to run DNS. As stated in 
the ``DNS and BIND'' book, third edition, ``Securing Your Name Server,'' page 
255:

Some of your name servers answer nonrecursive queries from other name servers 
on the Internet, because your name servers appear in NS records delegating your 
zones to them. ... You should make sure that these servers don't receive any 
recursive queries (that is, you don't have any resolvers configured to use 
these 
servers, and no name servers use them as forwarders). 
...

Now, I can go on and quote tens of other resources on proper DNS configuration,
however, I hope you get the picture.

> If I wanted I could change the current configuration and use
> Netvision's name servers to resolve domain names, and my own name
> server only as an authoritative name server.  It wouldn't cost me more
> money.  But would my server perform better?  I'm not sure.  Doron
> Shikmoni told me not to use Netvision's servers, and I guess he is
> right.

Doron is right, and you should not point your nameservers to use the NV
NSs, basically since every query will go over your link to them, which I
assume is not LAN.

--Ariel 
 --
 Ariel Biener
 e-mail: [EMAIL PROTECTED]
 PGP: http://www.tau.ac.il/~ariel/pgp.html

=================================================================
To unsubscribe, send mail to [EMAIL PROTECTED] with
the word "unsubscribe" in the message body, e.g., run the command
echo unsubscribe | mail [EMAIL PROTECTED]

Reply via email to