Windows 2008 Cluster and Getting the Private Network to Work

When clustering two servers together you may still want to set up private network connections. If you do hook a crossover cable and give it a different set of IPs from your domain you may find that the private network does not working. Pinging will return no responses. What you may have run into is that the Windows Firewall is interpreting your little private network as being 'Public' and so is block all communications in.

The solution depends on what flavor of w08 you are running. If you are running w08 you can go into the "Network and Sharing Center" and customize the network to be "Private" which will allow communication through. If you are running w08r2 it is not so simple. You have to go into Windows Firewall and explicitly tell it NOT to apply "Public" rules to the adapter you are using for your private network. 

Because a picture is worth a thousand words:

Windows 2008 (non-R2)

Windows 2008 R2