Overview

VMware Fusion’s networking configuration is a bit obscure and it is difficult to find information about it on the ‘net. I usually only need to achieve the following bits of config change, and they really only serve my need to tightly control all the things. I am posting this information here so that I never forget again.

Terminology

• host always refers to the Mac running Fusion. To run commands on the host, startup Terminal.app and start typing!
• guest always refers to the operating system running in a virtual machine within Fusion. To run commands on the guest, either log in via the VMware Fusion console or ssh your way into the guest.

NAT networking configuration

Changing the IP subnet for a VMware Fusion network

This is super-simple. Edit the following file:

$ sudo -e /Library/Preferences/VMware\ Fusion/networking

and make the obvious changes. For vmnet8, the NAT network, the config parameter is:

answer VNET_8_HOSTONLY_SUBNET 10.0.1.0

Then restart VMware Fusion networking:

sudo /Applications/VMware\\ Fusion.app/Contents/Library/vmnet-cli --stop
sudo /Applications/VMware\\ Fusion.app/Contents/Library/vmnet-cli --start

Using vmnet8 dhcpd to assign static IPs

This is useful if you do not want to mess with the DHCP setup of your virtual machine. So if you copy the virtual machine and boot it up on another host, you will get network access without having to mess around with /etc/network/interfaces. The disadvantage is that you have to do a bit of manual configuration of VMware Fusion, the documentation for which can be a bit obtuse. Note that if you copy the virtual machine the NIC MAC address changes, so you will need to re-discover the MAC address and reconfigure VMware whenever you copy a virtual machine.

1. Find the MAC address of your virtual NIC in the guest machine

ex.

$ ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:0c:29:b3:31:a0
inet addr:10.0.1.130 Bcast:10.0.1.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:feb3:31a0/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:464 errors:0 dropped:0 overruns:0 frame:0
TX packets:261 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:466580 (466.5 KB) TX bytes:20814 (20.8 KB)

HWaddr is the MAC address for the virtual NIC; in this example, the value is 00:0c:29:b3:31:a0.

2. Edit your vmnet8 dhcpd.conf file

On your Mac host:

$ sudo -e /Library/Preferences/VMware\ Fusion/vmnet8/dhcpd.conf

Most of this file is automatically generated. AFTER this comment:

####### VMNET DHCP Configuration. End of "DO NOT MODIFY SECTION" #######

add the following stanza:

host ubuntu {
    hardware ethernet 00:0c:29:1b:5a:98;
    fixed-address 10.0.1.7;
}

Note that you can choose whatever name you fancy to follow host. The fixed-address IP address must be in the IP range of the vmnet8 subnet, in this example the IP range is 10.0.1.0/255.255.255.0. The hardware ethernet setting is, predictably, the MAC address of the virtual NIC in the guest operating system.

3. Restart VMware Fusion services

In the host:

sudo /Applications/VMware\ Fusion.app/Contents/Library/vmnet-cli --stop
sudo /Applications/VMware\ Fusion.app/Contents/Library/vmnet-cli --start

4. Restart the guest OS

Reboot the guest OS, or restart its networking layer. For example, in ubuntu, either of these will work:

sudo service networking restart

or

sudo reboot

5. Closing thoughts

Do not forget to add a convenience line to your host’s /etc/hosts file, now that you have a nice shiny predictable IP!