Zentyal: Overriding some DNS entries for some external domains to internal ip

Question

Id like to overwrite public URLs to point to internal IP addresses using Zentyal DNS. The goal is for all requests to an address e.g. www.example.com to be routed to an internal server e.g. http://192.168.1.255.

This works when I alter the files in /etc/bind, but the changes are lost with each restart. I have tried to create a stub for these changes in "/etc/zentyal/stubs/bind" but the configurations changes are not recognized on module restart or reboot.

How do I make the BIND/DNS changes persist across module restarts, reboots and software updates?

Answer 1

I realised no BIND stubs exist, the configurations in /etc/bind are created from the DNS stubs in /usr/share/zentyal/stubs/dns/. I kludged a solution borrowing Ubuntu tips from -> https://www.redpill-linpro.com/sysadvent/2015/12/08/dns-rpz.html

Create in there a file called db.rpz with the following contents:

$TTL 60
@            IN    SOA  localhost. root.localhost.  (
                          2015112501   ; serial
                          1h           ; refresh
                          30m          ; retry
                          1w           ; expiry
                          30m)         ; minimum
                   IN     NS    localhost.

localhost       A   127.0.0.1

www.some-website.com    A        127.0.0.1

www.other-website.com   CNAME    fake-hostname.com.

make a "dns" directory in /etc/zentyal/stubs

sudo mkdir /etc/zentyal/stubs/dns

Copy "named.conf.local.mas" and "named.conf.options.mas" from "/usr/share/zentyal/stubs/dns/" to "etc/zentyal/stubs/dns" to cd /usr/share/zentyal/stubs/dns/

sudo cp named.conf.local.mas /etc/zentyal/stubs/dns
sudo cp named.conf.options.mas /etc/zentyal/stubs/dns

Edit named.conf.local.mas (inside /etc/zentyal/stubs/dns) and add this section:

zone "rpz" {
  type master;
  file "/etc/bind/db.rpz";
};

Edit named.conf.options.mas (inside /etc/zentyal/stubs/dns) and somewhere in the options { } section add the response-policyoption:

options {
  // bunch
  // of
  // stuff
  // please
  // ignore

  response-policy { zone "rpz"; };
}

Restart the DNS module in Zentyal.

sudo sudo zs dns restart

This will rewrite the "named.conf.options" and "named.conf.local" files in side "/etc/bind" each time the module is restarted (e.g on reboot or module restart). The changes should persist across reboots and Zentyal upgrades.