VMware

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It has been suggested that this article or section be merged with Emulating the XO/UsingVMware. (Discuss)


Emulation with VMWare

VMWare (Workstation, Player) is an emulator released as commercial software. The player version is distributed free of charge (Gratis). It runs on either Win32 or Linux host machines, allowing you to run OLPC images within the virtual machine. A Mac version is also available, VMWare Fusion, however this is not provided free of charge (a free 30-day evaluation is available).

You can decide either to emulate an XO via downloaded images, or to build a developer's desktop image starting from a stock Fedora 7. Both approaches are discussed here.

Developer's Desktop Emulation

You'll probably want two different Virtual Machines. For serious development of core system components, a Fedora 7 with sugar-jhbuild. For testing and working on activities, you will likely want to run the XO Emulator (see below).

For development on the core system, you need the Fedora 7 system, so you can use GIT for creating patches. With F7, you're also unlikely to lose your work accidentally while you can still easily run the latest version (using source-code-control is highly recommended). The XO image is nice, beacuse it is much more responsive than F7+Sugar-jhbuild. However, sound and networking may or may not work, depending on the image you are using.

The quickest way to get started creating a jhbuild (developer's desktop) is:

  • First get a preconverted XO image from are made available (don't worry that it is not the latest; anything less than 6 weeks old is perfect). Be sure to change networking to 'bridged' if you want to access the virtual XO using ssh from another machine in your network. Now you have something to play with, while getting the real environment. See the sections below for more instructions.
  • The next steps will take the better part of a day to complete, if not more on a slower machine (You'll be running an emulator within an emulator!) For Windows: if your machine was considered 'fast' two years ago, you'll do fine. For Macs: don't even think about this on a G4 or even a G5: use an Intel-Mac. On either platform: You can try this with 1GB of RAM in your machine, but 2GB is a more realistic minimum. 3GB is perfect.
  • So: Join one of the IRC channels! Sitting all alone while waiting for the install to complete is no fun :) You will probably want to start either in #sugar for hacking on activities or #olpc for core hacking. #olpc-content is about creating/maintaining materials (you don't actually need an F7 vmware for that!). A lot of people just hang out in two or all three of those. Ask if someone knows about a little thing to hack on. There are always buttons to be added, simple things to be done. Those will get you to learn the environment, really quickly.
  • Create a new virtual machine and do a base F7 install on it. Make sure you give the disk at least 15GB max size. If you have the disk space, preallocate it now. That will give you a twofold increase in performance. If you have more than 1GB of RAM, set the virtual machine to 800MB, if not give it 400MB. Give it access to all your CPUs too, if you have them (default is one). Don't worry about packages yet. That will come scripted in the next step. note: There is a preinstalled 'virtual appliance' F7 available via vmware.com, but you'll need to increase its disk size first. It maxes out at 4.7GB. 2GB short of a working sugar-jhbuild environment.
  • Now do everything on Sugar with sugar-jhbuild. Your home directory is a fine place. The update step will take long-ish, downloading 1.6GB of data (using compression so probably around 400MB in actual download). The build phase is correspondingly long, too: On a 2.4Ghz Core2 duo iMac with 3GB ram it took about two hours. YMMV.
  • Additionally, you can (and should!) look at http://dev.laptop.org for things to do. There are two 'beginner' links there.

Emulating the XO

An emulated XO image is recommended for developers working on Activities (as distinct from Sugar and other core libraries). It is also recommended for those who want to test their software or who may not have enough computer power to run a developer's image.

The XO images have the advantage of being faster than a "developer's desktop" image. They are also much easier to maintain (sugar-jhbuild can be quite time consuming). You should be sure to use source-code-control storing to another machine (such as your host machine) for all of your code so that you do not lose work when updating to a newer image.

You can use your host machine to edit files and "upload" them to your virtual XO via source-code-control or editor-based virtual file-systems.

Compatibility

  • Official OLPC build 616 is known to work under VMWare workstation 5 on Linux AMD64 with networking and (non-csound) sound with a workaround (sound service needs to be restarted)
  • Official OLPC build 602 is known to work under VMWare workstation 6 on Vista and MacOS using VMWare Fusion.
  • Official OLPC build 557 is known to work under VMWare with networking (tested on Linux AMD64 host w/).
  • A kernel driver (Ensoniq ES1371) has been added to allow sound support https://dev.laptop.org/ticket/3034.

Caveats

  • You will need to use ssh, rsync, or another standard Unix mechanism to share files with the image under the Player version of the software
  • On Linux, VMWare setup requires a package of kernel modules

Setup

The VMWare/VirtualBox images are converted from the official images using a simple downloading script. You can either download and convert the official images yourself or use a pre-converted image.

Downloading a Pre-converted Image

Pre-converted images are made available periodically to support those who do not have Qemu's tools installed on their workstations. Choose the .zip file for the version you require.

Read bug #3470 before choosing builds 578-581!

Building an Image from Scratch

  • Download an official devel-ext3 image (<thefile>.img.bz2)
  • bunzip2 <thefile>.img.bz2
  • use the qemu-img function from Qemu to convert the image into a vmdk file
    • qemu-img convert <thefile>.img -O vmdk <thefile>.vmdk

Now create a new VMWare "Machine":

  • "New Virtual Machine", "Typical", OS Type "Other Linux 2.6.x kernel"
  • Network Address Translation (NAT) networking (recommended, try others if you like)
  • Disk configuration (irrelevant, we're going to overwrite it)

Edit "Machine" Settings:

  • Memory 512MB (recommended for development work, 256 more closely simulates an XO)
  • Remove the auto-generated hard-disk
  • Add a new hard disk, "Existing Disk Image", choose <thfile>.vmdk
  • Ensure that audio is enabled

Configure

Once you have booted the machine, you will need to specify a name for yourself and choose an XO colour. You will then need to configure the collaboration server. To do this, pull up the developer's console, and use the "vi" editor to change the configuration file ~/.sugar/default/config to change the "server=" line to "server=olpc.collabora.co.uk".

When this is done, reboot. The virtual XO should now have networking support and should show you a network view with other XOs logged on.

Tips

  • To get access to the root console, that is, virtual console 1
    • You can use CTRL-ALT + space then F1, that is, hold down CTRL-ALT while you press the spacebar and then the F1 key. You can do the same with F3 to get back to your normal X session.
  • Use an Editor on your HOST machine to edit code. Much nicer user experience. Quite a few editors support 'remote' files using SCP, for example. Setup 'samba' in your virtual machine and you can just use network drives.
  • Install the VMWare tools when available. Really. Just do it.
  • Use full screen mode to make working with the emulated machine more pleasant.

OLPC Clones

VMware Workstation has a nifty feature called "Linked Clones." This enables users to deploy virtual machines based on the "template virtual machine" that take up very little space. For example, I can make a OLPC virtual machine, turn it into a template, make a clone, and the clone will take up ~6 megs of disk space when not running. When running, it will consume more diskspace as ram.

Why Are OLPC Virtual Machine Clones Useful?

It is now extremely easy to test mesh networking and networking activities in general. The folks at OLPC Austria have done something similar with qemu, but that requires additional software to manage a virtual ethernet network. VMware workstation provides more networking support out the box.

In addition, the clones would take less disk space than it would to run multiple instances of qemu images.

Creating the Template OLPC Virtual Machine

  • Follow the above steps for creating a OLPC virtual machine, but when done, do not boot it up. This is extremely important! Booting it up and making a clone of that will cause unpredictable behavior such as no setup username screen ever displaying.
  • Now, edit the virtual machine's settings and go to the options tab. Choose "Advanced" and check the "Enable template mode" checkbox and hit OK.
  • Go to the snapshot manager for this virtual machine and choose to take a snapshot in its powered off state. Give it a useful name like, "OLPC Base Template" with a description of perhaps "Not booted yet." Save this.
  • You now have a template VM for cloning!

Deploying Clones From The Template OLPC Virtual Machine

  • Select the template OLPC VM and choose to clone it.
  • In the dialog box that pops up, select next.
  • Choose the existing snapshot (It will be called "OLPC Base Template" if you followed the above instructions exactly) and hit next.
  • Choose "Create a linked clone" - This will greatly save on disk space.
  • Give the clone a name and a place to live in and click through.
  • Now you can boot the clone!

See Also

  • VirtualBox is an emulation system with similar performance and usage
  • Qemu is an Open Source emulation system
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