What impact does "duplicate name exists on the network" error have for a virtual machine?

Question

I have a project where multiple developers are using a copy of the same windows Virtual PC image (W2K3 SE SP2). Because our solution is tied to the machine-name (less than ideal, i know) all of the developers have the same machine name.

We use a VPN to connect to a remote system, upon connection we get the "Windows Error: A duplicate name exists on the network" error.

Since all development is happening locally, we're not dependent on other machines connecting to us -- only outbound connections.

I know it's best practice to change the machine name, but what's the reasoning behind this? What impact would this have?

Answer 1

The machine name in this case is used mostly for SMB/CIFS file sharing purposes. The problem with duplicate names is if you try to share files, there is no way to identify which host is which.

There may also be some other related effects, but I think if you are only working locally you shouldn't have any problems.

Answer 2

If you are doing all work locally on the VM, there is no reason why the machine name needs to stay the same.

I have run into a similar situation where I work. We were using Microsoft's trial version of SharePoint 2007 VM. Same error, no issues with development. The only thing I ran into was when I opened Internet Explorer to view the pages on the server by typing http://servername/page.aspx, I would hit another developer's VM. I had to use http://ipaddress/page.aspx to hit my own machine.

Answer 3

Well besides goofing up AD, DNS, Netbios or Netbeui...nothing.

Duplicate machine names is not a best practice. It can mess with file sharing, pinging, group policies, etc.

You have to ask yourself WHY they're doing this in the first place.