[[PageOutline]]

= Running apps in VirtualBox virtual machines =

BOINC's '''vboxwrapper''' program lets you run applications in VirtualBox virtual machines.
This eliminates the need to build app versions for different architectures,
and provides a stronger security sandbox than is otherwise available.

NOTE: Do not use software which uses a license that has a pay-per-use clause.

== Creating app versions ==

You must create app versions for each platform you want to support;
the app versions differ only in one file.

The application versions for a given platform are of plan class "vbox32"
(for 32-bit machines) or "vbox64" (for 64-bit machines),
and include the following files:

 * The VM image, in VirtualBox format.
  * Must have the '''copy_file''' attribute.
  * Must have logical name "vm_image.vdi".
 * The application executable to be run in the VM image.
  The logical name must be '''shared/boinc_app'''.
 * Other files needed by the application, all with logical names starting with '''shared/'''.
 * An XML job description file with logical name '''vbox_job.xml''' (see below)
 * '''vboxwrapper''', compiled for the platform.
 * All scripts and executables must have the execute permission set.
  These executables can be downloaded from the BOINC site (see below).

Include '''<dont_throttle/>''' in the version.xml file; VirtualBox does its own CPU throttling.

Typically you can use the same VM image for multiple applications.
This reduces network traffic and client disk usage.

The bitness of the vboxwrapper and VM image must match the plan class.
A 32-bit wrapper cannot use VirtualBox on a 64-bit machine. 

=== The job description file ===

The job description file has logical name '''vbox_job.xml'''
(its physical name should include a version number and other info).
It has following structure:

{{{
<vbox_job>
   <os_name>name</os_name>
   <memory_size_mb>N</memory_size_mb>
   [ <enable_network_access/> ]
   [ <enable_shared_directory/> ]
</vbox_job>
}}}
The elements are:

 '''os_name''':: the name of the guest OS as defined by VirtualBox, e.g. "Linux26", "Linux26_64", "Linux24", etc.[[BR]]
   To see a list of available os_names, type "vboxmanage list ostypes" at a shell prompt

 '''memory_size_mb''':: the amount of physical memory allocated to the VM, in megabytes.

 '''enable_network_access''':: if present, allow the VM to do network access.

 '''enabled_shared_directory''':: if present, create a directory that is shared
   between the host OS and the guest OS.
   Must be set if your application has input or output files.

== Requirements of the VM ==

The VM, when booted, must do the following:

 * If the applications has input or output files, mount the shared directory using

{{{
mount -t vboxsf shared /root/shared
}}}
 where "~/shared" is the path where the shared directory is to be mounted.
 In this case the VM must contain the VirtualBox "guest additions". Guest additions
 are required for shared folders to work or any special features of the virtualized
 hardware.

 * Run the application.

 * When the application is finished, shut down the VM
  (e.g., by running '''shutdown''' on Linux).

These steps are typically done by a '''startup script''' in the VM image.
An example startup script is given below.
This script runs the application by doing the following:
 * cd into the shared directory
 * execute '''boinc_app''', and wait for it to exit.

Using this script,
your application executable must have logical name '''share/boinc_app'''.
It may be a compiled program or a script that runs other programs.

Doing things this way, the VM image is independent of the application.
You can use the a single VM image for many applications.

== Creating jobs for VM apps ==

The input and output files of a VM app must

 * Have logical names starting with '''shared/'''.
 * Have the '''copy_file''' attribute

This causes the BOINC client to copy them to and from the '''slot/x/shared/''' directory.

== How it works: example ==

Using the example startup script, the steps in running a vboxwrapper app are:

 1. BOINC client
  * Create slot directory, say slot/0
  * Create '''slot/0/shared''', and copy input files there
  * Execute '''vboxwrapper''' in the slot directory
 1. vboxwrapper
  * Create and run virtual machine
 1. Virtual machine
  * Startup script
   * mounts '''shared''' directory
   * cd into shared directory
   * execute boinc_app
   * when boinc_app exits, shut down virtual machine
 1. vboxwrapper
  * delete virtual machine
  * call boinc_finish()
 1. BOINC client
  * copy output files from slot/0/shared to project directory

== Example startup script ==

The example startup script follows.
You can deploy it by appending to '''~root/.bashrc'''.
{{{
echo --- BOINC VM starting
sleep 5
}}}

The "sleep 5" gives you time to break into a console session via CTRL-C
if you need to make changes to the VM in the future.

{{{
echo --- Mounting shared directory
mount -t vboxsf shared /root/shared
if [ $? -ne 0 ]; then
    echo --- Failed to mount shared directory
    sleep 5
    shutdown -hP 0
fi

echo -- Launching boinc_app
if [ -f /root/shared/boinc_app ]; then
    cd /root/shared
    ./boinc_app
    shutdown -hP 0
else
    echo --- Failed to launch script
    sleep 5
fi
shutdown -hP 0
}}}

== Creating VM images ==

The easiest way to make a Linux VM is to install the network install of Debian within the VM.
You can find the netinst images [http://www.debian.org/distrib/netinst here].

Advantages:
 * Small install size
 * !VirtualBox guest additions installed by default

=== Role Selection ===

During install you'll be asked what role should this Linux machine be configured for.
Make sure all roles are unselected before continuing.

=== Updating Grub ===

If you want to speed up the boot process,
change the default timeout for grub by modifing /etc/default/grub:
{{{
GRUB_TIMEOUT = 0
}}}

After saving the update run:
{{{
update-grub
}}}

=== Updating Inittab ===

To configure Linux for automatic login you'll need to install
a different terminal handler.
mingetty works well for our purposes.

To install mingetty:
{{{
root@boinc-vm-image:/etc/default# apt-get install mingetty
}}}

Next you'll need to change the terminal handler assigned to the first virtual terminal.
Change line:
{{{
1:2345:respawn:/sbin/getty 38400 tty1
}}}

To:
{{{
1:2345:respawn:/sbin/mingetty --autologin root --noclear tty1
}}}

== Precompiled vboxwrapper ==
=== Windows ===
x86: [http://boinc.berkeley.edu/dl/vboxwrapper_6.20_windows_intelx86.exe.gz vboxwrapper_6.20_windows_intelx86.exe.gz]

x64: [http://boinc.berkeley.edu/dl/vboxwrapper_6.20_windows_x86_64.exe.gz vboxwrapper_6.20_windows_x86_64.exe.gz]

=== Mac ===
TBD
=== Linux ===
TBD

== Premade Linux VM Images ==

These VM images were built using the instructions for creating vm images and the example startup script.

x86: [http://boinc.berkeley.edu/dl/vmimagex86.vdi.gz vmimagex86.vdi.gz]

x64: [http://boinc.berkeley.edu/dl/vmimagex64.vdi.gz vmimagex64.vdi.gz]