{
"type": "virtualbox",
"guest_os_type": "Ubuntu_64",
"iso_url": "http://releases.ubuntu.com/12.04/ubuntu-12.04.2-server-amd64.iso",
"iso_md5": "af5f788aee1b32c4b2634734309cc9e9",
"ssh_username": "packer",
"ssh_wait_timeout": "30s"
}
## Configuration Reference
There are many configuration options available for the VirtualBox builder.
They are organized below into two categories: required and optional. Within
each category, the available options are alphabetized and described.
Required:
* `iso_md5` (string) - The MD5 checksum for the OS ISO file. Because ISO
files are so large, this is required and Packer will verify it prior
to booting a virtual machine with the ISO attached.
* `iso_url` (string) - A URL to the ISO containing the installation image.
This URL can be either an HTTP URL or a file URL (or path to a file).
If this is an HTTP URL, Packer will download it and cache it between
runs.
* `ssh_username` (string) - The username to use to SSH into the machine
once the OS is installed.
Optional:
* `boot_command` (array of strings) - This is an array of commands to type
when the virtual machine is firsted booted. The goal of these commands should
be to type just enough to initialize the operating system installer. Special
keys can be typed as well, and are covered in the section below on the boot
command. If this is not specified, it is assumed the installer will start
itself.
* `boot_wait` (string) - The time to wait after booting the initial virtual
machine before typing the `boot_command`. The value of this should be
a duration. Examples are "5s" and "1m30s" which will cause Packer to wait
five seconds and one minute 30 seconds, respectively. If this isn't specified,
the default is 10 seconds.
* `guest_os_type` (string) - The guest OS type being installed. By default
this is "other", but you can get _dramatic_ performance improvements by
setting this to the proper value. To view all available values for this
run `VBoxManage list ostypes`. Setting the correct value hints to VirtualBox
how to optimize the virtual hardware to work best with that operating
system.
* `http_directory` (string) - Path to a directory to serve using an HTTP
server. The files in this directory will be available over HTTP that will
be requestable from the virtual machine. This is useful for hosting
kickstart files and so on. By default this is "", which means no HTTP
server will be started. The address and port of the HTTP server will be
available as variables in `boot_command`. This is covered in more detail
below.
* `http_port_min` and `http_port_max` (int) - These are the minimum and
maximum port to use for the HTTP server started to serve the `http_directory`.
Because Packer often runs in parallel, Packer will choose a randomly available
port in this range to run the HTTP server. If you want to force the HTTP
server to be on one port, make this minimum and maximum port the same.
By default the values are 8000 and 9000, respectively.
* `output_directory` (string) - This is the path to the directory where the
resulting virtual machine will be created. This may be relative or absolute.
If relative, the path is relative to the working directory when `packer`
is executed. By default this is "virtualbox". This directory must not exist
or be empty prior to running the builder.
* `shutdown_command` (string) - The command to use to gracefully shut down
the machine once all the provisioning is done. By default this is an empty
string, which tells Packer to just forcefully shut down the machine.
* `shutdown_timeout` (string) - The amount of time to wait after executing
the `shutdown_command` for the virtual machine to actually shut down.
If it doesn't shut down in this time, it is an error. By default, the timeout
is "5m", or five minutes.
* `ssh_host_port_min` and `ssh_host_port_max` (uint) - The minimum and
maximum port to use for the SSH port on the host machine which is forwarded
to the SSH port on the guest machine. Because Packer often runs in parallel,
Packer will choose a randomly available port in this range to use as the
host port.
* `ssh_password` (string) - The password for `ssh_username` to use to
authenticate with SSH. By default this is the empty string.
* `ssh_port` (int) - The port that SSH will be listening on in the guest
virtual machine. By default this is 22.
* `ssh_wait_timeout` (string) - The duration to wait for SSH to become
available. By default this is "20m", or 20 minutes. Note that this should
be quite long since the timer begins as soon as virtual machine is booted.
* `vboxmanage` (array of array of strings) - Custom `VBoxManage` commands to
execute in order to further customize the virtual machine being created.
The value of this is an array of commands to execute. The commands are executed
in the order defined in the template. For each command, the command is
defined itself as an array of strings, where each string represents a single
argument on the command-line to `VBoxManage` (but excluding `VBoxManage`
itself). Each arg is treated as a [configuration template](/docs/templates/configuration-templates.html),
where the `Name` variable is replaced with the VM name. More details on how
to use `VBoxManage` are below.
* `vm_name` (string) - This is the name of the VMX file for the new virtual
machine, without the file extension. By default this is "packer".
## Boot Command
The `boot_command` configuration is very important: it specifies the keys
to type when the virtual machine is first booted in order to start the
OS installer. This command is typed after `boot_wait`, which gives the
virtual machine some time to actually load the ISO.
As documented above, the `boot_command` is an array of strings. The
strings are all typed in sequence. It is an array only to improve readability
within the template.
The boot command is "typed" character for character over a VNC connection
to the machine, simulating a human actually typing the keyboard. There are
a set of special keys available. If these are in your boot command, they
will be replaced by the proper key:
* `
[
"<esc><esc><enter><wait>",
"/install/vmlinuz noapic ",
"preseed/url=http://{{ .HTTPIP }}:{{ .HTTPPort }}/preseed.cfg ",
"debian-installer=en_US auto locale=en_US kbd-chooser/method=us ",
"hostname={{ .Name }} ",
"fb=false debconf/frontend=noninteractive ",
"keyboard-configuration/modelcode=SKIP keyboard-configuration/layout=USA ",
"keyboard-configuration/variant=USA console-setup/ask_detect=false ",
"initrd=/install/initrd.gz -- "
]
## VBoxManage Commands
In order to perform extra customization of the virtual machine, a template
can define extra calls to `VBoxMangage` to perform. [VBoxManage](http://www.virtualbox.org/manual/ch08.html)
is the command-line interface to VirtualBox where you can completely control
VirtualBox. It can be used to do things such as set RAM, CPUs, etc.
Extra VBoxManage commands are defined in the template in the `vboxmanage` section.
An example is shown below that sets the memory and number of CPUs within the
virtual machine:
{
"vboxmanage": [
["modifyvm", "{{.Name}}", "--memory", "1024"],
["modifyvm", "{{.Name}}", "--cpus", "2"]
]
}
The value of `vboxmanage` is an array of commands to execute. These commands
are executed in the order defined. So in the above example, the memory will be
set followed by the CPUs.
Each command itself is an array of strings, where each string is an argument
to `VBoxManage`. Each argument is treated as a
[configuration template](/docs/templates/configuration-templates.html).
The only available variable is `Name` which is replaced with the unique
name of the VM, which is required for many VBoxManage calls.