BIND

Splenden · 01-10-2007, 11:38 AM

Hi,

I have a VPS with 2 spare IPs to be used for nameservers. What I'm wondering is, all the tutorials I'm reading seem to be geared to having 2 servers hosting nameservers. I don't have two servers, but rather 1 server (a VPS) with 2 spare IPs for nameservers.

Do you know if there is a way to host 2 nameservers off of 2 IPs on one server?

Thanks!

Splenden

JimBass · 01-10-2007, 12:23 PM

You could install 2 instances of bind, and tell each instance to only listen on one IP address within named.conf.

That isn't a good idea however. You should have 2 nameservers at 2 seperate locations, that way if one looses power or internet connectivity, the other still can supply DNS info. With only one box and 1 access to the net, if your connection goes down, all of your DNS goes down.

Peace,
JimBass

Splenden · 01-10-2007, 01:09 PM

I understand. Unfortunately, I don't have another server to put DNS on. (Of course, if my DNS went down, Apache would too since it's on the same machine.)

I might try 2 instances of BIND. I'm only doing 2 NS servers to meet the DNS requirements from my registrar (2 nameservers).

Thanks!

Splenden

JimBass · 01-10-2007, 01:15 PM

Well, you don't need to run two instances of bind. You could have, but as long as you give DNS answers on the 2 addresses you give the registrar, you'll be fine. Just install bind once, and make sure it listens on all interfaces. Test it out with

Code:

dig yahoo.com @first.ip.address
dig google.com @2nd.ip.address

If you get answers for both, then the DNS is working on both interfaces.

Peace,
JimBass

Splenden · 01-10-2007, 01:26 PM

Is there a way to make it listen on 2 specific IP addresses rather than all IP addresses?

Thanks!

Splenden

trickykid · 01-10-2007, 01:27 PM

Quote:

Originally Posted by Splenden

I understand. Unfortunately, I don't have another server to put DNS on. (Of course, if my DNS went down, Apache would too since it's on the same machine.)

I might try 2 instances of BIND. I'm only doing 2 NS servers to meet the DNS requirements from my registrar (2 nameservers).

Thanks!

Splenden

JimBass is correct. Just point both your ns1 and ns2 at the registrar level to two IP's that the machine may have and just have Bind listen on all, should work instead of having two Bind's running.. that's just silly!

trickykid · 01-10-2007, 01:28 PM

Quote:

Originally Posted by Splenden

Is there a way to make it listen on 2 specific IP addresses rather than all IP addresses?

Thanks!

Splenden

Well, for DNS resolution though it's only technically going to use the two you have for ns1 and ns2.. but you can just easily block the others if you have other IP's with iptables just so port 53 isn't listening on all IP's.

JimBass · 01-10-2007, 01:36 PM

Yes, it is best to listen on everything.

You can restrict listening to given interfaces, but you probably have only a single interface with multiple addresses, so you can't easily restrict it. You can google for listen-on in named.conf, that will give you info, but there is no good reason to do that.

Peace,
JimBass

Splenden · 01-10-2007, 01:48 PM

IPtables. Great idea! Thanks everyone!

Splenden