vagrant-lxc

LXC provider for Vagrant 1.1+

Check out this blog post to see the plugin in action and find out more about it.

Features

• Vagrant's up, halt, reload, destroy, ssh, provision and package commands (box packaging is kind of experimental)
• Shared folders
• Provisioning with any built-in Vagrant provisioner
• Setting container's host name
• Port forwarding

Please refer to the closed issues and the changelog for most up to date information.

Requirements

• Vagrant 1.1+
• lxc 0.7.5+
• redir (if you are planning to use port forwarding)
• A bug-free kernel

On a clean Ubuntu 12.10 machine it basically means a apt-get update && apt-get dist-upgrade to upgrade the kernel and apt-get install lxc redir.

Installation

vagrant plugin install vagrant-lxc

Usage

After installing, add a base box using any name you want, for example:

vagrant box add quantal64 http://dl.dropbox.com/u/13510779/lxc-quantal-amd64-2013-05-08.box

Then create a Vagrantfile that looks like the following, changing the box name to the one you've just added:

Vagrant.configure("2") do |config|
  config.vm.box = "quantal64"
end

And finally run vagrant up --provider=lxc.

If you are using Vagrant 1.2+ you can also set VAGRANT_DEFAULT_PROVIDER environmental variable to lxc in order to avoid typing --provider=lxc all the time.

If you are on a mac or windows host and still want to try this plugin out, you can use the Ubuntu 12.10 VirtualBox machine I use for development.

Advanced configuration

If you want, you can modify container configurations from within your Vagrantfile using the provider block:

Vagrant.configure("2") do |config|
  config.vm.box = "quantal64"
  config.vm.provider :lxc do |lxc|
    # Same effect as as 'customize ["modifyvm", :id, "--memory", "1024"]' for VirtualBox
    lxc.customize 'cgroup.memory.limit_in_bytes', '1024M'
  end
end

This will make vagrant-lxc pass in -s lxc.cgroup.memory.limit_in_bytes=1024M to lxc-start when booting containers. This will override any previously value set from container's configuration file that is usually kept under /var/lib/lxc/<container-name>/config.

For other configuration options, please check lxc.conf manpages.

Available boxes

LINK	DESCRIPTION
lxc-raring-amd64-2013-05-08.box	Ubuntu 13.04 Raring x86_64 (Puppet 3.1.1)
lxc-quantal-amd64-2013-05-08.box	Ubuntu 12.10 Quantal x86_64 (Puppet 3.1.1 & Chef 11.4.0)
lxc-precise-amd64-2013-05-08.box	Ubuntu 12.04 Precise x86_64 (Puppet 3.1.1 & Chef 11.4.0)
lxc-sid-amd64-2013-05-08.box	Debian Sid (Puppet 3.1.1)
lxc-wheezy-amd64-2013-05-08.box	Debian Wheezy (Puppet 3.1.1)
lxc-squeeze-amd64-2013-05-08.box	Debian Squeeze (Puppet 3.1.1)

Please note that I'm currently using only the quantal x86_64 on a daily basis, and I've only done some basic testing with the others

There is a set of rake tasks that you can use to build base boxes as needed. By default it won't include any provisioning tool and you can pick the ones you want by providing some environment variables.

For example:

CHEF=1 rake boxes:ubuntu:build:precise64

Will build a Ubuntu Precise x86_64 box with Chef pre-installed.

Storing container's rootfs on a separate partition

Before the 0.3.0 version of this plugin, there used to be a support for specifying the container's rootfs path from the Vagrantfile, on 0.3.0 this was removed as you can achieve the same effect by symlinking or mounting /var/lib/lxc on a separate partition.

NFS synced folders

NFS shared folders are not supported and will behave as a "normal" synced folder so we can use the same Vagrantfile with VBox environments.

Current limitations

• The plugin does not detect forwarded ports collision, right now you are responsible for taking care of that.
• There is a hell lot of sudos involved and this will probably be around until user namespaces are supported.
• Does not tell you if dependencies are not met (will probably just throw up some random error)
• • bunch of other core features and some known bugs

Development

If want to develop from your physical machine, just sing that same old song:

git clone git://github.com/fgrehm/vagrant-lxc.git
cd vagrant-lxc
bundle install
bundle exec rake # to run unit specs

To run acceptance specs, you'll have to ssh into one of the development boxes and run:

bundle exec rake spec:acceptance

Using vagrant-lxc to develop itself

Yes! The gem has been bootstrapped and since you can boot a container from within another, after cloning the project you can run the commands below from the host machine to get a container ready for development:

# Required in order to allow nested containers to be started
sudo apt-get install apparmor-utils
sudo aa-complain /usr/bin/lxc-start
bundle install
cd development
bundle exec vagrant up quantal --provider=lxc
bundle exec vagrant ssh quantal

That should result in a container ready to rock. Once you've SSH into the guest container, you'll be already on the project's root. Keep in mind that you'll probably need to run sudo aa-complain /usr/bin/lxc-start on the host whenever you want to hack on it, otherwise you won't be able to start nested containers there to try things out.

Using VirtualBox for development

bundle install
cd development
# Pass in --provider=virtualbox in case you have VAGRANT_DEFAULT_PROVIDER set to something else
bundle exec vagrant up quantal
# A reload is needed to ensure the updated kernel gets loaded
bundle exec vagrant reload quantal
bundle exec vagrant ssh quantal

Protips

If you want to find out more about what's going on under the hood on vagrant, prepend VAGRANT_LOG=debug to your vagrant commands. For lxc-starts debugging set LXC_START_LOG_FILE:

LXC_START_LOG_FILE=/tmp/lxc-start.log VAGRANT_LOG=debug vagrant up

This will output A LOT of information on your terminal and some useful information about lxc-start to /tmp/lxc-start.log.

Help! I'm unable to restart containers!

It happened to me quite a few times in the past and it seems that it is related to a bug on linux kernel, so make sure you are using a bug-free kernel (>= 3.5.0-17.28). More information can be found on:

• https://bugzilla.kernel.org/show_bug.cgi?id=47181
• https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1021471
• https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1065434

Sometimes the dev boxes I'm using are not able to lxc-start containers anymore. Most of the times it was an issue with the arguments I provided to it for customization or the buggy kernel. If you run into that, rollback your changes and try to vagrant reload the dev box. If it still doesn't work, please file a bug at the issue tracker.

Similar projects

• vagabond - "a tool integrated with Chef to build local nodes easily"
• vagueant - "vaguely like Vagrant for linux containers (lxc)"

Contributing

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request