CERN Accelerating science



How do I report an error or a bug?

Tue, 07/05/2011 - 11:14 — Daniel Lombraña...

If you have found an error or a bug in the application, the experiments, the project, etc. please write a post about the error in the message boards so the vLHCathome administrators and volunteers can participate in solving the problem.

The virtual machine does not quit. How can I safely stop it?

Tue, 07/05/2011 - 10:04 — Daniel Lombraña...  (Updated July 2013, BS)

*** The following advice only applies to the old wrapper ***

If after quitting BOINC, the virtual machine continues running, you can safely stop it by running the following command in your computer:

VBoxManage controlvm BOINC_VM savestate

The next WU is failing and the previous one was running OK. What could be wrong?

Thu, 07/21/2011 - 09:16 — Daniel Lombraña...

*** OBSOLETE: old wrapper only **** (BS)

If you are still experiencing problems, go to the message boards and ask for more help.

VirtualBox crashes and does not respond at all to BOINC. What can I do?

Fri, 07/15/2011 - 10:01 — Daniel Lombraña...  (Updated July 2013, BS)

If the virtual machine named "boinc_wu_xxxx_..." in the VBox Manager window does not respond at all to BOINC (i.e. you suspend the BOINC task but the VM is still running) you can try the following steps to recover the project:

  1. Abort the running WU and exit BOINC. Then, you will have to manually kill or quit the VirtualBox process from a command line. It will be different in each operating system, but usually:
    1. In Mac OS X: you can kill it using the Terminal interface and running the kill -9 command to kill the PID of the process "VBoxHeadless.exe".
    2. In GNU/Linux: you can kill the VirtualBox process using your Desktop manager or from a terminal using the kill -9 command to kill the PID of the process called "VBox Headless".
    3. In Windows: open the Windows task manager and kill the VirtualBox process.
    4. Restart BOINC: it should receive a new clean WU and everything should be working OK again. If at this point you are still having problems, please use the message boards to get more help.
I'm getting lots of errors and I have BOINC installed as a service/daemon, is this a problem?

Thu, 08/04/2011 - 12:42 — Daniel Lombraña...

BOINC must not be installed as a service (Windows) or a daemon (GNU/Linux) because this project uses Virtual Machines. When BOINC is installed as a service or a daemon it runs as an unprivileged user and cannot run any virtual machine.

The best solution to solve this problem under Windows is to install BOINC disabling the Service option in the Windows installer.

Late news: BOINC Client 7.2.10 and above solve this problem for running as a service under Windows.

For GNU/Linux users the recommendation is to use the official BOINC GNU/Linux installer instead of the packaged ones for your distribution.

I'm getting the following message: Computation Error output file absent. What can I do?

Wed, 07/27/2011 - 10:33 — Daniel Lombraña...  (Updated July 2013, BS)

First of all, HAVE YOU INSTALLED VirtualBox ??

Next, check that your BOINC installation sets up the correct permissions for running VirtualBox. Recheck our information on "Installing BOINC".

If BOINC is correctly installed, the main reason for that message is that the wrapper fails to remove an old virtual machine (VM) after it has expired, and so cannot register a new VM for the next Work Unit (WU). This applies mainly to the older "CernVM wrapper" system, not the new "VBox Wrapper" system.

The best solution for cleaning your project files if you have to do it manually is:

  1. Abort the running WU.
  2. Quit BOINC (the core client should be not running).
  3. Open VirtualBox Manager, and remove the registered machine named "BOINC_VM" (or any VM's with names "boinc_wu_xxxx_xxx").
  4. Open VirtualBox Media Manager and remove the cernvm.vmdk virtual hard disk if it is registered.
  5. Launch BOINC again.
How can I debug the project, experiments, etc.?

Tue, 07/05/2011 - 11:11 — Daniel Lombraña...  (Updated July 2013, BS)

You have a full description of how you can debug the project here

The Virtual Machine uses my CPU all the time. How can I change this?

Tue, 08/09/2011 - 11:41 — Daniel Lombraña...

You can change how much CPU time is used by the Virtual Machine going into your account and changing the Preferences for this project -> Maximum CPU % for Virtual Machine. You can specify an amount between 0 and 100% (by default 100%), the save it and restart BOINC.

I installed BOINC in Windows with the "Protected Application Execution" option. Could this be a problem?

Tue, 08/09/2011 - 12:01 — Daniel Lombraña...

If you have installed BOINC with the Protected Application Execution option enabled, then you will not be able to run the project, and all the work units will fail. The reason is that when you install BOINC with that flag enabled, BOINC is run under an unprivileged user that cannot create, start, pause, resume virtual machines at all. Thus, the wrapper will not be able to run the required virtual machine of this project.

In order to solve it, please, reinstall BOINC with that option disabled.

I'm using a Proxy for my Internet connections. Could this be a problem?

Tue, 08/09/2011 - 11:58 — Daniel Lombraña...

If you only have access to Internet via a Proxy, you may get Compute Errors in BOINC, as the Virtual Machine needs direct connection to Internet. For the moment there is no solution, but we will try to fix it.

Message boxes keep popping up from Virtualbox. How can I remove them?

Thu, 08/11/2011 - 09:28 — Daniel Lombraña...

VirtualBox warns the user about how the keyboard and mouse will be captured if you click inside the window of the virtual machine. This message will pop up everytime you run a virtual machine unless you tick the "don't show this window again" option in the message box.

My keyboard and mouse do not respond to me. How can I get them back?

Thu, 08/11/2011 - 09:38 — Daniel Lombraña...  (Updated July 2013, BS)

If you click inside the console window of the Virtual Machine and the keyboard and mouse get "grabbed" in the window, then to release them, you have to press the Host Key (Right Ctrl) or (Right Cmd in Mac OS X). You can check which is the Host Key by clicking in: File->Preferences->Input

VirtualBox shows me the following runtime error message: "cannot access the kernel driver!" What can I do?

Fri, 08/12/2011 - 08:15 — Daniel Lombraña...  (Updated July 2013, BS)

(This is a Windows problem only).If you get that error it seems like your VirtualBox installation missed installing the vboxdrv.inf driver. Please first try to reinstall VirtualBox - if this does not solve the problem, go to C:\Program Files\Oracle\VirtualBox\Drivers\ and double click in the file vboxdrv.inf. After that, you should be able to run VirtualBox without problems.

BOINC fails to run any T4T work units. What can I do?

Tue, 07/05/2011 - 10:28 — Daniel Lombraña...  (Updated July 2013, BS)

There could be several possible options for this error, primarily:

(i) VirtualBox is not installed in your computer or

(ii) you have found a new bug in the system.

Some Windows XP users are reporting that by installing Visual C++ 2005 Redistributable Package the project starts working again. You can download this package for 32 bits from here and for 64 bits from here. These packages are official Microsoft solutions and they are free.

If you do have VirtualBox installed, review the FAQ and then ask in the message boards for help, so developers can review the error and help you.

Why my web browser is not supported?

Mon, 01/16/2012 - 15:09 — Daniel Lombraña...  (Updated July 2013, BS)

The web application provided in the virtual machine uses JavaScript, HTML5 and CSS3 to show the results and your BOINC credit, using technologies like JavaScript, JSON and HTML5.

If you cannot enable JavaScript in your browser's settings or your browser does not support HTML5 and/or CSS3, you will be missing a friendly user interface to the results:

  • an interactive gallery with all the figures from the simulations of your computer:
    • zoom in and out with a friendly interface,
    • browse the figures (next,previous and index) using shortcuts and without going back and forward to see other image,
    • swipe movement for flicking through images on touch devices,
    • etc.
  • and some BOINC statistics.

Here you have an screenshot of the web page with a free, modern and open source web browser like Mozilla Firefox or Google Chrome (but note that Safari versions 6+ and Internet Explorer versions 10+ do support our graphics):

You can still access the raw figures and BOINC stats data and the LOGs folder as you will get a warning with links to those resources.

Can I disable the VirtualBox window when running this project?

Mon, 01/16/2012 - 15:12 — Daniel Lombraña...  (Updated July 2013, BS)

Yes, you can.

The new VBox Wrapper runs in headless mode in any case, so there is no fixed console window.

If you still use the older CernVM Wrapper, please, go to your profile account in the Test4Theory web server. Then modify the project preferences by changing the value of the following field: Run Virtual Machine in headless mode: no to yes.

I have a multi-core system but BOINC only uses one core for the virtual machine. What could be wrong?

Mon, 01/16/2012 - 15:20 — Daniel Lombraña...  (Updated July 2013, BS)

First of all, please read: "Why the Virtual Machine is not using all my CPU cores?".

Apart fom the above information, there are more considerations as follows. In order to run a multi-core virtual machine, VirtualBox needs a set of specific chip extensions usually enabled by default in recent computers and laptops. However, some vendors disable these extensions in the BIOS configuration, so you will not be able to run a Virtual Machine with two or more cores.



If you want to solve it you will have to access the BIOS settings of your computer. Our recommendation is to read the manuals of your computer and check if there is a clear solution to enable this feature in your computer as every computer has a different set up for the BIOS settings. However, remember that this operation could be dangerous for your system if you modify something different than the virtualization extensions. If you do not feel comfortable modifying the BIOS settings, let the VM run with one core, as the wrapper should detect the problem and run with just one core.

My firewall is complaining. Which ports does this project use?

Tue, 08/02/2011 - 08:33 — Daniel Lombraña...

This project uses the following ports:

  • Jabber messaging which needs XMPP (port 5222),
  • Chirp (port 9094) for moving data in and out,
  • HTTP (port 80) and
  • HTTPS (port 443)

And if you want, you can grant access to the entire CERN network:


No other ports are used by the project.


What is VirtualBox?

Tue, 07/05/2011 - 09:39 — Daniel Lombraña...  (Updated July 2013, BS)

VirtualBox is a powerful x86 and AMD64/Intel64 virtualization hypervisor for enterprise as well as home use. A hypervisor allows your computer to host one or more Virtual Machines, running different operating systems than your own computer runs. This is essential for our Test4Theory project.
Not only is VirtualBox an extremely feature rich, high performance product, it is also the only professional solution that is freely available as Open Source Software under the terms of the GNU General Public License (GPL) version 2.
What is Virtualization?

Tue, 07/05/2011 - 11:08 — Daniel Lombraña...

Virtualization, in computing, is the creation of a virtual computer that can run an operating system, applications, etc. within your real hardware. You can obtain more information about this topic in the Wikipedia.
What is CernVM?

Wed, 07/06/2011 - 08:44 — Daniel Lombraña... CernVM is a Virtual Software Appliance for the participants of CERN LHC experiments. The Appliance represents an extensible, portable and easy to configure user environment for developing and running LHC physics software both locally, on Grids and on Clouds, independently of Operating System software and hardware platforms (GNU/Linux, Windows, MacOSX).

The goal is to remove a need for the installation of the experiment software on each target platform, and thus to minimize the number of platforms (compiler-OS combinations) on which experiment software needs to be supported and tested. Visit the CernVM homepage for further details.

Why do we need a virtualization application?

Tue, 07/05/2011 - 10:51 — Daniel Lombraña...

This project runs very large CERN software packages with complex dependencies that cannot be easily ported to all the volunteers' operating systems (Windows, GNU/Linux and Mac OS X). For this reason, we use a virtualization solution, which enables us to run complex codes independently of your platform. Additionally, using virtualization adds an extra layer of security, as if something goes wrong in the code execution this will not affect your computer.

The virtual machine is resetting/rebooting itself, is this the expected behavior?

Tue, 09/13/2011 - 14:04 — Daniel Lombraña...  (Updated July 2013, BS)

The Co-Pilot software detects if your virtual machine is in an unrecoverable state (due to unexpected errors, lost of connectivity, etc.), and reboots/resets it to start the execution of new experiments again. This will not affect at all your work unit or BOINC credit. However, it should only happen very rarely - if it is frequent you almost certainly have a network connectivity problem.

Why the Virtual Machine is not using all my CPU cores?

Fri, 08/05/2011 - 12:16 — Daniel Lombraña...  (Updated July 2013, BS)

The new VBoxWrapper does not support more than 1 core currently.

(In any case, due to the limited use of multi-threading for the current application, only about 1 and a half cores can be utilized in practice).

Our older CernVM Wrapper does support multi-core systems. However, we only used at most two cores, because the current experiments will not benefit at all from 3 or more cores. Thanks to this, your BOINC client will be able to run other projects in the free and available cores of your computer.

I've updated VirtualBox and now I cannot see the VM console. How can I fix it?

Tue, 12/11/2012 - 09:49 — Daniel Lombraña... (Updated July 2013, BS)

If you have upgraded VirtualBox, you will need to also upgrade the VirtualBox Extensions Pack, otherwise you will not be able to see again the Virtual Machine Console. After upgrading the extensions, cancel the running WU and request a new one, this will allow T4T to configure the VM correctly with the new extensions.


Where can I find help?

Tue, 07/05/2011 - 10:31 — Daniel Lombraña...

In this FAQ and by all means asking and participating in the message boards of the project. We have a great community that will try to help you.
<p>Why are we using desktop computers instead of the Grid?</p>

The computing needs of the LHC, especially when it comes to comparing various theories with experimental results, are enormous. Basically, the physicists' appetite for computing power expands to fill all available resources, because there are always more theories to test than there are computers to test them with.

Since budgets are constrained, especially in these economically difficult times, access to volunteer resources is seen by CERN as a great opportunity to expand computing capacity. We'll never replace the Grid's core function of managing the data mountains, but we could augment its computing power considerably. While the LHC World-Wide Computing grid is used at full capacity to handle the analysis of LHC data, there is need for additional capacity for simulations of LHC physics, ranging from theory to simulations of detectors as well as design improvements for future accelerators.

It's also clear to everyone in our community that getting the public more directly involved in LHC physics has great outreach benefits as well. So we see this as a win-win situation. And who knows, perhaps one day we'll be able to announce an important discovery that will have been made in part thanks to the volunteers. That would be cool!

What do I need to participate in this project?

Tue, 07/05/2011 - 10:30 — Daniel Lombraña...

You need a computer connected to the Internet with at least 512MB of RAM and 9GB of free hard disk space. It can run Windows, MacOSX or Linux. Additionally you will have to install two applications: BOINC and VirtualBox. Please, read carefully our installation guide.

Does this project support GPUs?

Tue, 08/09/2011 - 12:25 — Daniel Lombraña...

For the moment this project does not use GPUs for running the experiments. Additionally, the GPU code could not work as we are accessing the hardware via a virtual machine.

Is it possible to configure the maximum amount of data that can be downloaded/uploaded by the project per month?

Tue, 09/13/2011 - 11:48 — Daniel Lombraña...

The BOINC transfer at most network preference is not supported for the moment. If your ISP has a limitation in the bandwidth that you can use each month, bear in mind that the virtual machine will continue downloading/uploading data when needed.

Are any of my personal data sent to CERN when I install the software? What information about my machine is sent?

Thu, 10/13/2011 - 09:54 — Daniel Lombraña...

You will only have to provide a user name and an e-mail, nothing else is required. The information that is sent about your machine is the hardware specifications: CPU type, RAM and disk space, OS version, etc.

I tried to install it, but it was too complex I gave up...

Thu, 10/13/2011 - 09:57 — Daniel Lombraña...

We know it, and for this reason we are working together with the BOINC and VirtualBox communities to simplify the whole process to set up the software and join us. It will be interesting if you can tell us where you have difficulties, please use the forums, so we can try to fix them for the next releases.

Physics experiments

What experiments are we running?

Tue, 07/05/2011 - 10:02 — Daniel Lombraña...

You will be helping scientists by running simulations of particle collisions on your home computer. If you are interested in the details, please read the details of each project.
Are the current results already used or are we only crunching test units?

Thu, 08/11/2011 - 09:22 — Daniel Lombraña...

We are already processing real data which is submitted to a central database. Please, see the explanation of each experiment.

All the work units run for 24 hours regardless of the CPU speed. What is wrong?

Thu, 08/11/2011 - 09:26 — Daniel Lombraña...

All the work units are designed to run for a fixed period of time of 24 hours. The difference appears in the amount of work done inside the virtual machine.

Can I simply shut down my computer or is a special procedure necessary?

Mon, 10/17/2011 - 11:13 — Daniel Lombraña...  (Updated July 2013, BS)

We recommend to exit BOINC before powering off the computer, because the VBox Wrapper will capture that exit signal, and will try to save the virtual machine and avoid canceling the WU. This is not necessary when suspending or hibernating the computer.

Which scientific applications are you using for running the simulations?

Wed, 12/14/2011 - 11:51 — Daniel Lombraña...

We are using Herwig++, Pythia 6, Pythia 8, Sherpa and Vincia.

How can I see the progress of the experiments?

Tue, 07/05/2011 - 11:03 — Daniel Lombraña...  (Updated July 2013, BS)

If you want to see what is going on in the Virtual Machine: 

1. If you are running the new "VBox Wrapper":

  • You can view VM console screens via a Remote Desktop Protocol (RDP) client by pressing the button "Show VM Console" appearing in the BOINC manager GUI for a running Test4Theory Task. The control keys Alt-Fx select alternative VM console screens - see "Debugging the application".

(Non-Windows users can download and install a free RDP client such as CoRD for Mac OS X, or FreeRDP for Linux).

(NOTE: "Show VM Console" will only work if you installed the VirtualBox Extension Pack for your version of VirtualBox. Remember to quit BOINC before you update VirtualBox or the Extension Pack).

  • You can view Graphics and logs: Another new BOINC Manager GUI button "Show graphics" is provided to view the graphics and log output from the VM, using any up to date browser version (including Firefox, Chrome, Internet Explorer 10 or Safari 6). A window of your default browser will be automatically used.

2. If you are running the old "CernVM Wrapper":

  • You can view VM console screensThe VM runs in "headfull" mode by default (unless you change your BOINC preferences to suppress it). So you only have to click inside the BOINC_VM window to see the initial boot sequence followed by the CoPilot scheduler output when a job is received or returned. You can then see the job output files in the second terminal window by pressing ctrl-alt-F2 (this changes between OSes, please read the debugging page).
  • You can access the graphics and logs of the experiments within the VM via a friendly web page: http://localhost:7859/ via your web browser.

In the terminal output or in the web application you will see the output of different Monte Carlo event generators (Herwig++, Pythia 6, Pythia 8, Sherpa, Vincia).

Are you planning to create a screen saver to show the progress of the experiments?
Thu, 10/13/2011 - 10:02 — Daniel Lombraña...  (Updated July 2013, BS)

There is no screensaver provided (or planned) for Test4Theory.

But you can see many of the computed results via a friendly web application which is provided in the virtual machine. In order to see the results you will have to press the "Show graphics" button in the BOINC Manager (if you are using the new VBox Wrapper) or (for the old CernVM Wrapper) open the following web page: http://localhost:7859/

For more details, see "How can I see the progress of the experiments?".

Here you have an screenshot of it up and running:

Demo of the application

How many physics jobs are run per BOINC Work Unit?

Wed, 07/25/2012 - 09:41 — Daniel Lombraña...  (Updated July 2013, BS)

The average CERN job run time is around 1 hour, including the delays between downloading/uploading libraries, results, etc.

So, taking into account that each BOINC Work Unit will be running in your computer for 24 hours, on average each BOINC Work Unit will simulate in your virtual machine around 20 CERN physics jobs, or about 2 million collision events.