Default IP address for DNS records Automatically detect external address<- Not Working


I have a little problem with my virtualmin. As I am in a testing phase right now and experimenting with virtualmin. I have a setup in which my ADSL modem is connected to the router and I am using centos5. So I am getting an IP Which is manually placed in the Centos Configuration so DHCP doesn’t provides me an IP.

Everything is working fine the BIND Dns server is also working fine. I have “” domain which have an option as child nameservers in which i put my external IP address as my host name of the machine on which virtualmin is hosted is “”.

Now problem comes whwn the external ip changes. When the external IP changes virtualmin does not alter the DNS records of my previously created virtual servers. Even if the Default IP address for DNS records Automatically detect external address is checked. SO i have to manually go to the dns records of each virtual servers and change it from there. This seems so time consuming.
My servers are setup on LAN ip so i don’t need to change the default IP of the server but atleast DNS recoreds should be changed in order for working of the domains.

So i need help that virtualmin should alter the old DNS records from my new external address. I don’t want to use services like dyndns as i own a domain of my own and the registrar provides me with child nameservers change. So I can point the child name servers IP to my hosatname’s IP (i.e: “”)

“Automatically detect external address” does not mean that Virtualmin detects changes of that address and updates records for you. It means that at the time of Vserver creation (and only then), it queries the external address and uses it.

DNS on dynamic addresses is a considerable issue. Not only would you need to modify your zone files, but also the registration at your hoster and your NIC, which both hold IP addresses for the authoritative nameservers for your domains.

My suggestion would be to use only systems with static IP addresses for authoritative nameserver purposes.

but the problem is that currently my isp is not providing static ip on my home plan.
Is there any way from which I can run virtualmin on dynamic ip without changing the dns records everytime the ip is changed.
Even the Allowed sender IP addresses contains the NetworkIP; and the old External IP
.Please tell me how can i run it.

Well, all other services besides DNS can be operated okay on a NAT home machine, since the external IP can be queried and dynamically updated then, as long as the nameserver is static.

But, as I outlined, I don’t see a way to operate authoritative nameservers on dynamic IPs without changing them in the NIC and your zones each time you get a new one. Which, additionally, constitutes the problem of caches and TTLs. It usually takes a few hours for changes in a NIC to propagate throughout the Internet.

Nameservers are simply not meant to be operated on non-static IPs.

You might rather wish to use some external DNS service which offers dynamic updates to your zones through a(n automated) web interface or via DNS protocol means, and which has static IPs for the authoritative zones.

Or you rent some very small and cheap VPS from a hoster and slap a Linux with only BIND and Webmin on it, and use that as authoritative and maybe your home machine as hidden master.