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Retrieving local IP assigned from VPN DHCP

Hi,

My computer is connected to Internet via a Router.
The Router is connected to my ISP.
I connect to an Office WAN via a VPN connection.

Using Java code:
I need to retrieve the Dynamic IP address assigned to my computer by the VPN DHCP.

I tried to use the code sample bellow but it returns the LAN IP address.
My knowledge of the package java.net.* is limited.

Any help would be greatly appreciated.

Thanks

InetAddress address = InetAddress.getLocalHost();
System.out.println(address.toString()); // returns 10.0.1.1 (the LAN IP assigned by the router)

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CEHJ

You could make a connection to whatismyip.com and read the response

CEHJ

Actually http://www.whatismyip.com/automation/n09230945.asp

ASKER CERTIFIED SOLUTION

Mick Barry

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deve-lopez

ASKER

whatismyip returns the IP of the web gateway when accessed while on VPN.

I found the method to obtain all the IPs assigned.
I just have to pick the good one from the list.
Attached is the code for anyone who is interested.

Thanks

    public static void main(String[] args) {
        // TODO code application logic here
        try {
            //InetAddress address = InetAddress.getLocalHost();
            //InetAddress address = InetAddress.getByName("lvignals-us64.us.oracle.com");
            InetAddress address[] = InetAddress.getAllByName("lvignals-us64.us.oracle.com");
            for (int i=0; i<address.length; i++) {
                System.out.println(address[i].toString());
            }
        } catch (UnknownHostException e) {
            System.out.println("LVI: Could not determine this computer address..."+e.toString());
        }
    }

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Mick Barry

> Actually http://www.whatismyip.com/automation/n09230945.asp

you don't need to do that, and it won't return what you want anyway

Mick Barry

> InetAddress address[] = InetAddress.getAllByName("lvignals-us64.us.oracle.com");

you don't need to know the hostname, see the code I posted above

CEHJ

>>whatismyip returns the IP of the web gateway when accessed while on VPN.

Yes, that's usually what you need

deve-lopez

ASKER

In this case what was needed was the IP of the specific laptop running the code when that laptop is connected via VPN:

InetAddress address[] = InetAddress.getAllByName("machinename.domain.com");

does exactly what is needed, it returns the list of IP used by each active network adapter on the laptop.

Mick Barry

what I posted above should provide that, did you try it?

deve-lopez

ASKER

Thanks