Secondary Configuration for BIND9

"zone" statement in named.conf
same statement as the primary server
Example for a secondary server of "kame.net"
    zone "kame.net" {
        // act as a secondary server
        type slave;
        // specify the secondary file
        file "sec/kame.net.zone";
        // primary server's addresses
        masters { 192.0.2.1; };
    };