This tip describes a way of getting the vmxnet.sys driver working in the Server Core Edition of Windows 2008. Here are the instructions:
“For those unfamiliar with Server Core, it is a command line only version of Windows Server 2008 (formerly Longhorn). I have been trying to install this on ESX 3.0. On the GUI version of Windows 2008 server, VMWare tools must be installed to get the NIC working. Server Core, however, is command line only. VMWareTools is a GUI installation so this is not an option for Server Core. The workaround is to transfer VMWareTools (contained in a file called windows.iso) from your ESX server to a local drive. This can be done using Winscp. Use Virtual Center to mount the windows.iso file as a CDROM drive in the Server Core VM. The driver files are located in \Program Files\VMWare\VMWare Tools\Drivers\VMXNet\w2k of the windows.iso file. The command used to install the drivers is
C:\Windows\System32>pnputil -i -a vmxnet.inf
Microsoft PnP Utility
Processing inf : vmxnet.inf
Successfully installed the driver on a device on the system.
Driver package added successfully.
Published name : oem2.inf
Next check the installation of the driver. Vmxnet should be displayed near the end of the list.
ws2ifsl Winsock IFS driver Kernel 18/04/2007 04:52:40
vmxnet VMware Ethernet Adapte Kernel 22/04/2006 23:13:11
You can then enable remote access of Server Core with the command.
netsh advfirewall set allprofiles settings remotemanagement enable
To disable the firewall.
netsh advfirewall set allprofiles firewallpolicy allowinbound,allowoutbound”