If your Virtualmin server is on an internal private network, and all HTTP traffic is forwarded to it via a firewall or proxy, you should set this field to the IP address via which it is accessed externally, such as that of your firewall or router. When this option is set, the address entered will be used for all DNS records that would normally contain the real address, such as `www`, `mail` and `ftp`.

By default, the DNS records automatically generated for this virtual server will contain the IP address that it is assigned by Virtualmin. However, in some cases this address may not actually be the one you want web and mail clients on the Internet to connect to.