A Power User's Guide to VMware Fusion

A Power User's Guide to VMware Fusion

Disclaimer: This is a personal document and is not official or endorsed by VMware. Feedback, suggestions, and edits are welcome.

This document is primarily intended for people who have used Fusion for a  while and are curious about how to do more advanced things. People who  have used other VMware products may be interested in this as a reference  for where to find settings. This document describes configurations  which have no UI settings and are

not supported, but are still useful.

This document assumes you are familiar with A Beginner's Guide to VMware Fusion.

Important: Whenever you do file operations (move, copy, edit, delete, etc.) to a VM,

make sure it is powered down and Fusion isn't running. You don't want to change the data out from under Fusion.

If you want to be notified of changes and additions to this document,  you can use the "Receive email notifications" action in the sidebar on  the left. Please use the comments below only for things specific to this  document; general questions are better off in the

discussion section.

A tool you may find handy is

VMX Extras, which is a GUI way to change some of these settings.

Fit Full Screen

Note: This setting is no longer necessary in Fusion 2.0, as this is the default.

When you switch to fullscreen mode in a guest without tools installed or  a guest which changes the screen resolution, you might notice black  borders around the screen since the host resolution remains the same.  You can tell Fusion to scale the guest to the host's resolution by  editing /Users/yournamehere/Library/Preferences/VMware  Fusion/preferences to include the line

pref.autoFitFullScreen = "fitHostToGuest"

If the preferences file doesn't exist, create it as a plain text file.  If the autoFitFullScreen line exists, replace it or comment out the old  line.

Boot Delay

Fusion's BIOS flashes by very quickly - this is good for normal use  (optimize the common case!) but annoying if you want to change a BIOS  setting. You can slow down the boot process by adding the following line  to the .vmx:

bios.bootDelay = "3000"

You can of course change this number; the units are on the order of  milliseconds (e.g. "3000" adds approximately 3 seconds delay).

You can also force the VM to enter the BIOS on the next startup by adding the following line to the .vmx:

bios.forceSetupOnce = "TRUE"

The line will automatically change to FALSE at startup, so the regular boot device will be used on subsequent restarts.

In Fusion 3.0, an easier way to change the boot order (the most common  reason you'd want to get into the BIOS) is via Virtual Machine >  Settings > Advanced > Startup Device.


Fusion 2.0 introduces vmrun, a way to interact with virtual machines  through the command line. It's located in /Library/Application  Support/VMware Fusion/vmrun; run it with no arguments for help. An  example of some Automator actions which use vmrun is in Automator Actions


vmrun does not exist in Fusion 1.x, but you can get some similar  functionality by using Applescript's UI scripting, for example like

Re: Fusion's handling of Fullscreen is driving me INSANE!.

Additionally, you can tell Fusion to take action on certain signals by  adding either (or both) option to the .vmx (for just that VM) or  ~/Library/Preferences/VMware Fusion/config (for all your VMs):

signal.suspendOnHUP = "TRUE"
signal.powerOffOnTERM = "TRUE"

You might also be interested in the guest power scripts, which depend on  Tools being installed and are run inside the guest when it powers  on/powers off/suspends/wakes from sleep. To see where these scripts are,  open the Tools and select the Scripts tab.

Headless Mode

As the Beginner's Guide said, the vmware-vmx process does the real work  of running the virtual machine while the Fusion UI process handles input  and drawing. If you don't need the UI process, you can kill the UI  process after you start the VM (e.g. ctrl-option-clicking the Fusion  Dock icon and Force Quitting). The vmware-vmx process should continue to  run in the background. You can reconnect to it by starting Fusion again  and opening the VM.

In Fusion 2.0, an easier way is to run the following command in a Terminal Window:

defaults write com.vmware.fusion fluxCapacitor -bool YES

This will add a View menu item, "Headless". If you use this option, you  probably should also use the signal config options mentioned in the  Scripting section of this document to allow you to safely shut down the  physical machine without having to reconnect to the virtual machine.

I believe the VM continues running even if you log out, since the vmware-vmx process is root-owned.

The fluxCapacitor option was removed from Fusion 3.0 due to  rearchitecting of the rendering engine; we did not have time to make  sure that headless mode still worked. We realize it's something that  some people find useful. In the meantime, force quitting the UI or  invoking Fusion directly should work.


Dave Parsons has written a good guide to custom network settings:

How to modify Fusion network settings whitepaper, as well as scripts to manage custom settings:

Advanced Networking Configuration - Tokamak Networking Scripts for VMware Fusion

Note that Fusion 3's networking configuration is a little different, so you need an updated version of the scripts:

Re: Scripts to manage Fusion network settings

Share Guest Internet Connection With Host

WoodyZ has written a good guide for setting this up:

Share Windows XP Guest Internet Connection with OS X Host HOWTO

Static IP address

This only applies to NAT and host-only modes; bridged mode does not involve Fusion's DHCP server.

You might want a particular guest to always receive the same IP address via Fusion's DHCP server:

Re: DHCP reservations please

Alternately, by default Fusion's DHCP server reserves the range  x.y.z.3-x.y.z.127 (where x.y.z is the vmnet1 or vmnet8 subnet) for  static IPs - simply set the guest to use a static address in this range  (the exact method to do this will depend guest-specific).

Arbitrary MAC address

Fusion 2.0 allows you to use arbitrary MAC addresses, not just the range  assigned to VMware. In addition to changing the MAC address in the .vmx  file to the one you want, you also need to add the following line:

ethernet0.checkMACAddress = "FALSE"

This is easier in Fusion 3.0. You should be able to set the MAC address  via Virtual Machine > Settings > Network > Advanced options.

Guest OS networking without allowing Host OS to get an IP address

Unless you use something like a USB network dongle to bypass the host  entirely, the host network stack must be on to some extent in order for  the guest to have network connectivity. However, the host does not have  to be fully on the network, e.g. it doesn't have to have an IP address. ehendrix

wrote up instructions in Re: Connect Windows VM to network without OS X joining network?

(I don't think ehendrix first person to do so, but I can't immediately find older ones).

VNC Server

Like Workstation, Fusion has a built-in VNC server. This allows you to  connect to the guest without having a VNC server installed in the guest -  useful if a server doesn't exist for the guest or if you need access  some time when a server would not work (say during the boot process).  It's also good in conjunction with Headless Mode.

The VNC server is set up on a per-VM basis, and is disabled by default.  In Fusion 3.0; VNC settings are under Virtual Machine > Settings >  Advanced > Other. For older versions of Fusion, add the following  lines to the .vmx:

RemoteDisplay.vnc.enabled = "TRUE"
RemoteDisplay.vnc.port = "5901"

You can set a password with RemoteDisplay.vnc.key; details for how to  calculate the obfuscated value given a plaintext password are in

Compute hashed password for use with RemoteDisplay.vnc.key.

Note Previous revisions of this document incorrectly mentioned  that you could use a plaintext RemoteDisplay.vnc.password. This option  was in previous versions of Workstation but got removed in favor of  RemoteDisplay.vnc.key; it was not added back to Fusion until 2.0. The  obfuscated RemoteDisplay.vnc.key is preferred.

If you want more than one VM set up in this manner, make sure they have unique port numbers.

To connect, use a VNC client pointing at

host-ip-address:port. If  you connect from a different computer, you may have to open a hole in  the OS X firewall. If you use Leopard's Screen Sharing.app on the same  computer as Fusion, don't use port 5900 since Screen Sharing refuses to  connect to that.

Swap Alt (a.k.a. Option) and Windows (a.k.a. Command) keys

Mac and PC keyboards have different positions for the Alt/Option and  Windows/Command keys. If you're using a PC keyboard or have years of PC  muscle-memory, you can tell Fusion to swap these keys by adding the  following line to ~/Library/Preferences/VMware Fusion/config

mks.keyboard.swapAlt = "TRUE"

If the config file doesn't exist, create it as a plain text file.

This may not work in Fusion 2.0b2 and later, because Fusion's keyboard  mappings have changed. Instead, set this mapping Fusion's Preferences.


You might have noticed that some USB devices, such as keyboards and  mice, do not show up in the Virtual Machine menu or in the status bar.  By default, Fusion screens out Human Interface Devices (HID) because if  you attach your mouse/keyboard to a VM, you may have no way to get back  out (shutting down the guest may work, and if you've configured Fusion  to not automatically connect, unplugging/replugging should work, but if  you don't have this set and the guest crashes, you're out of luck). A  similar problem exists if you use a Bluetooth mouse/keyboard and attach  the Bluetooth adapter to the guest - don't do that either!

This masking is a problem for other devices such as tablets or mice with  lots of buttons, since they are also HID and therefore don't appear in  the list. If you want to use pressure sensitivity or other advanced  features, you need to attach the device to the guest. To get HID entries  to appear, add the following line to the .vmx:

usb.generic.allowHID = "TRUE"

If you use this setting, I would recommend disabling Virtual Machine  > Settings > USB > Automatically Connect USB Devices so that  you have some way to get a mis-connected device back (unplug and  replug). Remember not to connect your only keyboard/mouse to the guest!

Example instructions for using a tablet with an Ubuntu guest:

Instructions: enable wacom pressure sensitive tablet in Ubuntu 7.10, Leopard & VMware Fusion 1.1

"Two" computers in one

By now you know that Fusion lets you run multiple OSes at once, but it's  limited because only one person can be using them at a time. What if  you could separate them even more so that the host and the guest could  be used by different people simultaneously? You can combine the USB HID  setting with software cursor rendering to do this! While you could  achieve a similar effect by combining VNC/headless mode, this method  does not require additional physical computers as clients. Major caveats  include:

  • The host is still in control (so if OS X goes to sleep, the virtual  computer will not be usable, Exposé will affect the guest window, etc.)
  • You will need enough hardware resources to handle both host and guest
  • The guest cursor isn't quite as smooth as normal (but is still quite usable)

To use this tip, you'll need a second keyboard/mouse for the guest and  preferably have a second monitor. I would recommend disabling Virtual  Machine > Settings > USB > Automatically Connect USB Devices so  that you have some way to get a mis-connected device back (unplug and  replug). Start by adding the following lines to the guest:

svga.noHWCursor = "TRUE"
usb.generic.allowHID = "TRUE"

Connect the second keyboard/mouse to the guest, and optionally move the  guest to the secondary monitor and go fullscreen. Since the host mouse  can still wander over to the guest (get back out with ctrl-cmd on the  host keyboard), if you use a second monitor, I suggest telling OS X that  the monitors are offset so it's harder to do, e.g. go to System  Preferences > Displays > Arrangement and drag the displays so they  are arranged as follows:


You can extend this for even more virtual computers, though your hardware requirements will go up too.


Note: This setting provides no benefit on Nehalem or newer processors.  The benefit of VMI is simpler page mapping, but Nehalem processors  implement this efficiently in hardware. VMI support will be removed from all our products at some point in the future.

VMware proposed the VMI specification as a vendor-independent method for hypervisors to talk to guests about  certain things common to all hypervisors. VMI is part of the standard  Linux kernel since 2.6.22, though it might not be enabled by default in  your distro of choice. Enabling VMI speeds up guest system calls, improves timekeeping, and reduces overhead - of course, improvement varies by workload.

To do this, add the following line to the .vmx:

vmi.present = "TRUE"

For example, with 32-bit Ubuntu 7.04, if you've done this correctly, the  dmesg output should contain the line "Booting paravirtualized kernel on  vmi" instead of "Booting paravirtualized kernel on bare hardware"

Note that VMI does not work with 64-bit guests. On newer machines, it is  also unlikely to help, as the pain point it was created to address has  been eliminated due to improvements in hardware-assisted virtualization.

USB Logs

You might remember from Information Gathering for VMware Fusion that Fusion is able to log USB traffic. We've released an open source  (and unsupported) tool for visualizing USB logs generated in this  manner: http://vusb-analyzer.sourceforge.net/

GDB Server

Like Workstation, Fusion has a built-in GDB server. This allows you to  debug the guest without having to run kdb or recompile your kernel (I  think this is for Linux guests, or at least guests you can use GDB  with). You will need a kernel with symbols for your distro and be  familiar with how to use gdb. There is also untested support for  record/replay, which lets you do interesting things like stepping backward through a program.

Depending on the guest, add the appropriate line to your .vmx:

32-bit guests 64-bit guests

debugStub.listen.guest32 = "TRUE"


debugStub.listen.guest64 = "TRUE"

32-bit guests 64-bit guests

Once you've gotten to the guest to where you want to debug, use gdb to connect from the host (or other computer) with

32-bit guests 64-bit guests

target remote yourmachost:8832


target remote yourmachost:8864

32-bit guests 64-bit guests

Note yourmachost can be localhost.

In GDB, load up the kernel with symbols:

file yourkernelfilehere

(substituting the appropriate file, e.g. vmlinux-2.4.21-27.EL.debug) and  you're ready to debug the kernel. Debugging applications takes a little  more work, see the following links for more details:


Tags (2)

You should note in the Paravirt section that it's only the 32-bit Ubuntu 7.04 which supports paravirt -- the 64 bit version currently does not (although this is supposed to be remedied in the next release IIRC).

The USB HID section currently ends in "However, this is a problem for other devices such as tablets, since", with no further text.

Thanks for pointing those out, I'm not sure what I was thinking when I posted. It is (currently) an open wiki, though, so you can make changes yourself Smiley Happy

Silly me -- I didn't even notice. I admittedly haven't taken in all the new functionality of the new forums software, so I never even noticed it was Wiki-ized :P.

The "Fit Full Screen" section says to set autoFitFullScreen to "fitHostToGuest" and that "other valid values" are "fitHostToGuest" and "none". Presumably one of those "fitHostToGuest" references should be a reference to "fitGuestToHost", but I don't know which one (I still don't understand the functionality of this pref, despite having read about it and its possible values on several occasions).

Thanks for this info, but I can't find an important piece: Where is the .vmx file? I don't see it alongside the vmwarevm file or Library/Preferences/VMware Fusion.

See : Where to Find Things. The .vmx file is inside the .vmwarevm bundle.

The UI scripting link under Scripting is dead.

Can we add information about Alt and Windows key swapping in the VM? Its useful to know since I tell OSX to swap the keys on my Windows keyboard.

One thing that I find smart is this... I don't see any other such tips, so here goes:

DISABLE Windows native ability to smooth LCD Screen fonts using its ClearType trick. This is a subtle trick that relies on the fact that LCDs are full of red, then green, and then blue pixels (left to right, RGB displays). Mac OS uses a similar technology called Font Smoothing. Well, hopefully you know how to turn off Windows' ClearType if you are using it, because the instant that I did so while running Fusion, I instantly got a better looking Windows XP desktop. It would appear that using both OS's smoothing ends up with some red and blue edges on text so don't do both!! See .

Many of these features can also be configured by opening it in VMware Workstation 6.

Thanks for posting these useful hints! I'm using VMware/Fusion for the first time today, and already I have a Red Hat development system up and running.

I'm having trouble with the Alt key, though. I've turned on mks.keyboard.swapAlt, and it only works intermittently, which is unfortunate because the Alt key is critical to us emacs users.

I have a friend who is an X Windows hacker, and I borrowed a program from him that prints out keyboard events as they come in. Sometimes Command is mapped to Alt, and sometimes it's mapped to Ctrl. It seems to depend on which key gets pressed next. If I type "Command-A", it's showing up in the guest OS as "Ctrl-A", whereas "Command-B" shows up as "Alt-B". After some experimentation, I found that the Command key is correctly getting mapped to Alt for most letters, but gets mapped to Ctrl for these: A C F P Y X and Z.

Sometimes Command is mapped to Alt, and sometimes it's mapped to Ctrl.

While the virtual machine is powered off, try adding the following line to the .vmx:

pref.mapMacShortcutKeys = "FALSE"

1.1.1 added some remapping, which sounds exactly like what is interfering with your situation.

Thanks for the quick reply!

Setting pref.mapMacShortcutKeys in the .vmx file didn't make any difference, but putting it in ~/Library/Preferences/VMware Fusion/preferences did the trick (as mentioned in the thread "Disabling the new remapping of CommandC/CtrlC in Fusion 1.1.1".

This comment basically pertains to the Beginner's Guide, but it seems to be maxed out with comments. Basically, I am not getting the full "block diagram" picture. From this guide, it sounds like everything is memory resident - the VM, the Guest OS, the Guest applications and the Guest files. But I know that can't be. So just what resides on the virtual disk, and what resides on a chosen physical disk. I want to maximize the latter. Also, somewhere there was a reference to Bluetooth only being able to function with one OS at a time (Host or Guest). Does this mean I won't be able to use my wireless (i.e., Bluetooth) keyboard and mouse with the VM? Note, I also read the Getting Started and Mobility docs available for download. It would be helpful if the full documentation were similarly available.

I have Virtual Windows XP Pro on a 2 GH Mac Mini, with 2 GB of memory. I am running XP thru VMWare. Last night, I upgraded XP to SP2. Will "Dragon Speaking Naturally 10" work on my system?

I've tried adding

signal.suspendOnHUP = "TRUE"

signal.powerOffOnTERM = "TRUE"

To my virtual machine without changing my system settings. However any virtual machine that's started via launchd on my system startup (using the vmrun command) doesn't shut down. I checked out my vmx file, it seems once an auto snapshot runs it deletes these settings. Is there a way to set these on the vmware daemon itself, not just my user or the vmx file?

Thank you for these tip and sorry if this is a novice post or has been already addressed, my searches haven't turned up a solution yet. My issue is that I want to map one of my MacOS drives to a Letter. I cannot seem to get this to keep. In the VM (Windows 7) I have the mapped network drive to "X:" but upon reboot it is disconnected. And will not reconnect. I have to disconnect and reconnect and works fine again until the next reboot.

Mapping the Shared drive it seems to pick a scheme of Z:\ and moved backward assigning letters randomly based on how it detected the share at that boot - yes I have seen the devices walk or flop letters.

And on the mapping of the drive, I do specify a user login & password credentials and click on the remember box.

So truly how can I assign a share or a drive to a letter drive and have it stick?

How do I get headless back in Fusion 3.0, I tried to flip the same switch again, and it doesn't seem to have turned it on?


You can put comment lines into the vmx file. Prefix them with the "#" character, and VMware Fusion ignores rest of the line. I don't know if it's possible to put some text on a line, then a "#", then a comment on the same line.

I haven't found a VMware reference for this aspect of vmx file syntax. However, I found it mentioned in another forum post, and in my experience it works.

With respect to:

"Two" computers in one

I have a 3 monitor setup and have twin mice and keyboards.

Looking at "mouse & keyboard profiles" would there be any possibility to "hardlink" a specific mouse and keyboard set to a specific virtual machine?

I see a mouse & keyb profile can be assigned to a specific vm.

It would be extremely interesting to link a USB.HID within a profile.

Any ideas?



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