Create the zone key used for the transfer (IPs can be used, but it’s not as secure)

$ dnssec-keygen -a HMAC-MD5 -b 128 -n HOST zonetransfer

-a HMAC-MD5
The encryption procedure used (here HMAC-MD5)
-b 128
The length of the key (in the example, 128 bits)
-n HOST
The type of key
zonetransfer
Name of key

Include the key into the server config

in named.conf:

key “name-ofzone-com” {
algorithm hmac-md5;
secret “eoifl2349304rrjabwqA==”;
};

Configure the zone

zone “name.ofzone.com” { type master; file “/zones/master/name.ofzone.com.db”; allow-transfer { key name-ofzone-com;}; };

this uses the defined name of the key