whmcsDNSManager/modules/addons/DNSManager2/mgLibs/custom/dns/submodules/bind9/sampleZoneFile.txt

$ORIGIN {$domain}
$TTL {$ttl}
@ IN {$ttl} SOA {$mname} {$rname} 1 {$refresh} {$retry} {$expire} {$ttl}
@ IN {$ttl} A {$ip}
@ IN {$ttl} NS {$mname}