pfSense

The topic has been dealt with before and marked as done in #1327.
But in the current version, the zone parameter is missing again in the ouputfile /var/etc/nsupdatecmds0.
Maybe not all DNS Server affected, but the free DNS Provider dynv6.com need the zone parameter for a successful update.

https://dynv6.com/docs/apis

The easiest way is to add one line in the services.inc for the update instructions and set the zone to 'host' like:

/* generate update instructions */
                $upinst = "";
                if (!empty($dnsupdate['server'])) {
                        $upinst .= "server {$dnsupdate['server']}\n";
                        $upinst .= "zone {$dnsupdate['host']}\n";
                }

But it is much better to set the zone in the GUI, or to add a custom field to set additional options to avoid problems with other configurations.