public function getHostname(): HostnameInterface
    {
        if ($this->myHostname !== null) {
            return $this->myHostname;
        }

        // If no hostname is present, create a standard "in-addr.arpa" hostname from IP address.
        $ipAddressParts = $this->myIpAddress->getParts();

        return Hostname::fromParts([
            strval($ipAddressParts[3]),
            strval($ipAddressParts[2]),
            strval($ipAddressParts[1]),
            strval($ipAddressParts[0]),
            'in-addr',
        ], 'arpa');
    }