BIND9, DynDNS, Multiple RRs

[Theophanis Kontogiannis]

Hi Chris,

Thank you for your e-mail.
Indeed I do give to my two DSL connection separate names i.e. A.dyndns.biz
and B.dyndns.biz.
Sorry for my bad syntax.

However Ι do not see a way to do CNAME based load balancing for www.abc.biz

If it goes both to CNAME A.dyndns.biz and CNAME B.dyndns.biz, then I get the
error that initiated this post.

Obviously I cannot create A records for www.abc.biz, since the server is
hosted behind two dynamically assigned IP addresses.

Once more thank you All for your time.

Sincerely,

Theophanis Kontogiannis




-----Original Message-----
From: bind-users-bounce at isc.org [mailto:bind-users-bounce at isc.org] On Behalf
Of Chris Buxton
Sent: Tuesday, September 23, 2008 3:04 AM
To: Theophanis Kontogiannis
Cc: bind-users at isc.org
Subject: Re: BIND9, DynDNS, Multiple RRs

First, do not use CNAME's for your name server names. That means, the  
following is wrong and will not work reliably:

abc.biz.       NS     dns1.abc.biz.
dns1.abc.biz.  CNAME  a.dyndns.biz.

Second, there's no reason to give the same name to both DSL  
connections. Just because it's the same server doesn't mean the  
outside world needs to see it as one server with two (public) IP  
addresses. Use two names.

abc.biz.       NS     a.dyndns.biz.
abc.biz.       NS     b.dyndns.biz.

Chris Buxton
Professional Services
Men & Mice

On Sep 22, 2008, at 2:54 PM, Theophanis Kontogiannis wrote:

> Hello All,
>
>
> I have my DNS server, serving my .biz zone, NATed behind 2xDSL  
> routers /
> connections.
>
> The DNS is running on Centos 5 and bind-9.3.4-6.0.2.P1.el5_2.
>
> The DSL modems (I have two connections) are using DynDNS since the DSL
> connection is provided with dynamic DNS allocations.
>
> We assume that modem A gets declared on DynDNS as "a.dyndns.biz."  
> and modem
> B as "b.dyndns.biz.".
>
>
>
> What I try to do, is to make my NATed DNS, master for my domain (let  
> us call
> it abc.biz.)
>
>
>
> On the registrar I have to declare that my primary DNS for abc.biz.  
> is the
> DNS accessible through either DSL modem.
>
>
>
> I define dns1.abc.biz. as the primary DNS.
>
> However since this a DynDNS registered IP, I have to define  
> dns1.abc.biz. as
> a CNAME to "a.dyndns.biz.".
>
> But there are two DSL connections for redundancy and load balancing.
>
> So if I also define dns1.abc.biz. as a CNAME to "b.dyndns.biz." then  
> I get
> the error:
>
>                "multiple RRs of singleton type"
>
>
>
> I googled a bit, and found out that after BIND 9.1 the multiple-cnames
> directive got forced obsolete.
>
>
>
> Is there any way to succeed in what I try with BIND9?
>
>
>
> If I have to write the zone file in a different way, can you please  
> explain
> the way, since it is not obvious to me?
>
>
>
> Thank you All for your time,
>
>
>
> Theophanis Kontogiannis
>
>
>
>
>
>
>
>