Private IP Address Question


I’m a little confused as to how to change the IP address of a virtual server that has a dedicated IP.

I thought it would be vm >> Addresses and Networking >> Change IP Addresses. But it says this is just for “non private IP virtual servers”.

Is it edit virtual server >> configurable settings >> external IP address? The ‘help’ text for this seems to suggest it’s for something different.

My server is VM pro on CentOS 6


To change the IP for one Virtual Server, you can go into Server Configuration -> Change IP Address.

From there, you can add your new IP to “New IP address” in the “Use private address” field.


Hi Eric

I only see a field for “Use private IPv6 address”.

Perhaps I have to go to webmin >> network configuration first, and add the IP address there before it will appear as an option?

Nope, you don’t need to add it in Webmin first.

In Server Configuration -> Change IP Address, you should see an option to add both “New IP address” as well as “New IPv6 address”.

I have a few questions regarding your setup:

  1. What Virtualmin version are you using?

  2. What Linux distribution and version do you have?

  3. How did you perform the Virtualmin installation – was it with the script?


I am on CentOS Linux 6.2 Linux 2.6.32-71.29.1.el6.x86_64 on x86_64 fully patched + 3.90 Pro. VM installed by install script.

I have checked on my other production server and it’s the same. What I notice is this:

  1. If a virtual server is on a shared IP, then there is an option “Use private address”.

  2. If the virtual server is already using a private address, then that option is not there. The options are either “Keep private address” or go to shared IP address. You cannot enter a new private IP address.

This works: First change the server with private IP to use a shared IP. Then the option to change to private IP is available. When I tested that, there did not seem to be any problems.

i.e. Needs a two-step process. You can’t directly change one private IP to another.

What is a private IP? I have a server that has 5 IP’S. What is a shared vs. private IP?


A private IP is an IP address that’s only allowed to be used for just one domain – this is often used when giving a domain an SSL certificate.

A shared IP can be used for any number of domains.


Thanks Andrey as always.

How can we create a private IP? Does a private IP mean that it is a separate NIC?

I have one NIC with 6 IP’s bound to it such as eth0:0, etho:1 etc. Now all these IP’s show up in the shared IP dropdown.

Can you advise?


It uses an ethernet alias, such as what you described above. So if your main IP is on eth0, it would create an alias “eth0:0”.

To setup a domain with a private IP, you can go into Server Configuration -> Change IP Address, and set the desired IP there.