topic Re: DNS SLAVE problem in Operating System - Linux

DNS SLAVE problem

'chris' — Tue, 29 Nov 2005 06:46:15 GMT

hi

on my linux DNS master for ch.domain.net,
I've created a SLAVE ZONE for the root domain: domain.net

zone "domain.net" {
type slave;
file "/var/cache/bind/domain.net.hosts";
masters {
212.X.X.25;
212.X.X.26;
};
};

it works well, the root Zone will be synchronized, but I have following problem:

the master dns servers will be reached over the vpn tunnel.
if the vpn tunnel goes down, I cannot nslookup any server from this Zone.

howto make this zone available when the vpn tunnel is down ?

I have BIND 9.2.4

kind regards
chris

Re: DNS SLAVE problem

Steven E. Protter — Tue, 29 Nov 2005 07:39:16 GMT

Shalom Chris,

On the master server:

Do you have this code in named.conf ??

options {
directory "/var/named";
// query-source address * port 53;
allow-transfer { localhost; 10.1.10.1;};

The slave servers may not be getting any information.

For the slave server to work while the vpn tunnel is down, it must have the allow-transfer options correct and it must be reachable while the vpn tunnel is down.

SEP

Re: DNS SLAVE problem

Sergejs Svitnevs — Tue, 29 Nov 2005 08:11:01 GMT

Your slave nameserver is going to be *constantly* trying to contact the Internet root servers. When you have "forward only" enabled, then the nameserver will use the
forwarders to get the root server information.
So, you should just add "forward only;" to the options { } section of your named.conf on slave machine.

Regards,
Sergejs

Re: DNS SLAVE problem

Ivan Ferreira — Tue, 29 Nov 2005 13:30:10 GMT

What is the error when you do nslookup or dig to query the slave server?

Do you have the slaves listed as DNS servers on the client configuration?

Re: DNS SLAVE problem

'chris' — Tue, 29 Nov 2005 17:56:27 GMT

Master DNS is WIN2000

Slave is linux

I changed on the SLAVE from:

forwarders { 83.X.X.10; 83.X.X.11; 83.X.X.12; };
forward first;

to:

forwarders { 83.X.X.10; 83.X.X.11; 83.X.X.12; };
forward only;

is it correct now ?

SLAVE DNS servers are listed on the client configuration

greetings
chris

Re: DNS SLAVE problem

Steven E. Protter — Wed, 30 Nov 2005 04:42:01 GMT

Chris,

How you are doing it is not how we're doing it in my shop.

That doesn't mean it won't work, just that I'm not totally familiar with your methodology.

A typical slave configuration by me:

zone "blah.com" {
type slave;
file "blah.com.zone";
masters {
10.xx.xx.xx;
};
};

I suggest at this point you test.

BIND 9.2

My setup is different as both DNS servers sit in a DMZ and serve the public internet and transfer data to a server inside the firewall.

Good Luck.

SEP

Re: DNS SLAVE problem

Ivan Ferreira — Wed, 30 Nov 2005 06:42:30 GMT

Also, ensure that in the Windows DNS console, you have enabled the "BIND Secondaries" option.