DNS Zone options

2005090901      ; serial number
5M      ; refresh
1M      ; retry
604800  ; expire
10M     ; minimum TTL

example.com fragment from named.conf defines this server as a zone master 192.168.0.2 is a stealth server NOT listed in a NS record

zone "example.com" in{
    type master;
    also-notify {192.168.0.2;};
    file "pri/pri.example.com";
    // enable slaves only
    allow-transfer {192.168.23.1;192.168.23.2;);
};

SLAVE

options {
  directory "/var/named";
  // version statement for security to avoid hacking known weaknesses
  version "not currently available";

  // allows notifies only from master
  allow-notify {192.168.0.1};

  // disables all zone transfer requests
  allow-transfer{"none"};

  // Closed DNS - permits only local IPs to issue recursive queries
  // remove if an Open DNS required to support all users
  // or add additional ranges
  allow-recursion {192.168.3.0/24;};
};

example.com fragment from named.conf defines this server as a zone slave

zone "example.com" in{
        type slave;
        file "sec/sec.example.com";
        masters {192.168.23.17;};
};