====== Setup Raspberry Pi (Raspbian) as DNS Slave ======
 --- //[[colm.carew@errigal.com|Colm Carew]] 2017/08/11 08:30//
Ensure the pi has a scotty user who has sudoer access
This tutorial assumes you 10.91.100.71 is the master DNS and that 10.5.5.15 is the IP of the slave

SSH to the pi as scotty 
  * sudo apt-get update
  * sudo apt-get install bind9 bind9utils
  * sudo mv /etc/bind/named.conf /etc/bind/named.conf.bk
  * sudo nano /etc/bind/named.conf <code>// This is the primary configuration file for the BIND DNS server named.
//
// Please read /usr/share/doc/bind9/README.Debian.gz for information on the
// structure of BIND configuration files in Debian, *BEFORE* you customize
// this configuration file.
//
// If you are just adding zones, please do that in /etc/bind/named.conf.local

include "/etc/bind/named.conf.options";
include "/etc/bind/named.conf.local";
include "/etc/bind/named.conf.default-zones";
include "/etc/bind/named.conf.errigal-zones";
</code>
  * sudo nano /etc/bind/named.conf.options <code>options {
        listen-on port 53 { 127.0.0.1; 10.5.5.15; };
        listen-on-v6 port 53 { ::1; };
        directory "/var/cache/bind";
        allow-query     { localhost; 10.5.5.0/24; 192.168.123.0/24; };
        recursion yes;
        dnssec-enable yes;
        dnssec-validation no;
        dnssec-lookaside auto;

        // If there is a firewall between you and nameservers you want
        // to talk to, you may need to fix the firewall to allow multiple
        // ports to talk.  See http://www.kb.cert.org/vuls/id/800113

        // If your ISP provided one or more IP addresses for stable
        // nameservers, you probably want to use them as forwarders.
        // Uncomment the following block, and insert the addresses replacing
        // the all-0's placeholder.

         forwarders {
              8.8.8.8;
         };

        //========================================================================
        // If BIND logs error messages about the root key being expired,
        // you will need to update your keys.  See https://www.isc.org/bind-keys
        //========================================================================

        auth-nxdomain no;    # conform to RFC1035
};</code>
  * # Note please replace 10.5.5.15 in the above file with whatever IP you want as the DNS Slave
  * sudo nano /etc/bind/named.conf.errigal-zones <code>// be authoritative slave for the Errigal forward and reverse zones

zone "err" IN {
        type slave;
        file "/var/cache/bind/forward.errigal";
        masters { 10.91.100.71; };
};

zone "100.91.10.in-addr.arpa" IN {
        type slave;
        file "/var/cache/bind/reverse.errigal";
        masters { 10.91.100.71; };
};

zone "crc" IN {
        type slave;
        file "/var/cache/bind/forward.crown";
        masters { 10.91.100.71; };
};

zone"30.10.in-addr.arpa" IN {
        type slave;
        file "/var/cache/bind/reverse.crown";
        masters { 10.91.100.71; };
};
zone "ext" IN {
        type slave;
        file "/var/cache/bind/forward.extenet";
        masters { 10.91.100.71; };
};

zone"104.214.10.in-addr.arpa" IN {
        type slave;
        file "/var/cache/bind/reverse.extenet";
        masters { 10.91.100.71; };
};

zone "atc" IN {
        type slave;
        file "/var/cache/bind/forward.atc";
        masters { 10.91.100.71; };
};
zone "atc-rev" IN {
		type slave;
		file "/var/cache/bind/reverse.atc";
        masters { 10.91.100.71; };
};

</code>
  * ssh to the master dns (qadb2) and 
  * sudo nano /var/named/chroot/etc/named.conf
  * # Ensure that <code>allow-transfer  { localhost; 10.5.5.50; 10.5.5.15;  192.168.123.211; }; # Slave DNS Servers IP</code> has your slave ip
  * # If not add it and save and 
  * sudo service named restart
  * # ssh back to the pi
  * sudo reboot
  * ls -l /var/cache/bind/ 
  * # Ensure froward and reverse for crown, errigal and extenet are present
  * # if encountering any issues please run 
  * sudo tail -f /var/log/syslog
  * # On the pi to see if there are any issues transferring down the files
  * # If no issues then thats it you should now be able to set this pi as a DNS