Introduction

OpenVPN project uses ​Buildbot to help increase code quality. Buildbot is a Python application that can work in either master or slave mode. The buildmaster is the core server which accepts connections from buildslaves and tells them what they should do. Typically the clients fetch latest sources and report any build problems to buildbot which in turn informs developers via email. In software engineering this is called ​Continous integration and helps prevent build problems go unnoticed for extended time periods. The clients (buildslaves) can and should run on a variety of hardware / OS platforms. For the server (buildmaster) the OS choice is largely irrelevant.

As buildbot is a general-purpose (build) automation tool, it can also be used to automatically build packages for each buildslave architecture and then push them to a central repository for users to download. However, this adds significant amount of complexity and is prone to breakage. Therefore other means are used now to provide snapshots. It would be fairly easy to integrate code checking tools into the build process.

As the number of buildslaves can easily get out of hand, the OpenVPN project can make use of your help - see below for details.

Buildbot is described in more detail in the ​Buildbot manual.

Setting up the VPN connection

Our buildbot (buildmaster) is protected by OpenVPN. To connect your buildslave to it you need:

1. Active ​OpenVPN community services user account
2. Properly configured OpenVPN client
3. Membership in the appropriate LDAP group
4. Certificate authority (CA) key for the VPN
5. TLS-auth (TA) key for the VPN

You need to do 1. yourself. The rest will be taken care of for the most part by Samuli, our community manager at openvpn.net. He can also be reached at #openvpn and #openvpn-devel channels as "mattock".

Setting up a buildslave

Overview

Setting up a buildslave requires a few steps:

1. Make sure you can build OpenVPN manually
2. If you want to automatically build packages (e.g. deb/rpm) for your platform, you need to be able to do it manually first. Consult your OS'es documentation for more details.
3. ​Install buildbot requirements.
4. Download and install buildbot using one of the methods described ​here. More instructions are available ​here. You should install Buildbot 0.7.12 which the buildmaster is using.
5. Configure buildslave

Installing buildbot

Installing buildbot using easy_install

Probably easiest way is to install buildbot is by using ​easy_install: it should be available your OS'es software repository. Using easy_install will keep buildslave isolated from your OS'es package management and take care of dependencies for you. It is easiest (but ​not necessary) to run easy_install as root:

First switch to root account, e.g. using sudo or su:

$ sudo -s

Next test that easy_install should work as expected:

$ easy_install -n buildbot==0.7.12

If all went well, install buildbot for real:

$ easy_install buildbot==0.7.12

Once buildslave is installed you can and should switch to an ordinary user account.

Configuring the buildslave

Buildslave configuration is covered thoroughly in the official buildslave setup instructions:

• ​http://buildbot.net/buildbot/docs/0.7.12/#Creating-a-buildslave

List of existing buildslaves

Here's a comprehensive list of Buildslaves already running (as of Sep 2011). There can be several buildslaves that have the same OS/architecture combination, but this is seldom necessary.

Operating system	Version	Architecture	24/7	Connection tests	Provided by	Notes
Debian	5 (lenny)	i386	No	No	mattock
Debian	5 (lenny)	amd64	Yes	No	mattock
Debian	6 (squeeze)	i386	No	No	mattock
Debian	6 (squeeze)	amd64	Yes	No	mattock
Ubuntu	10.04	i386	Yes	No	mattock
Ubuntu	10.04	amd64	No	No	mattock
Fedora	15	i386	Yes	No	mattock
Fedora	15	amd64	No	No	mattock
Scientific Linux	6.x	?	Yes	No	dougy	Partially configured
FreeBSD	8.2	amd64	Yes	No(t yet)	cron2	nearly operational

List of build permutations

At the moment (Sep 2011) each buildslave builds OpenVPN using all unique combinations of the following:

• Branches:
  • "master" branch from openvpn.git
• Build flags:
  • --disable-crypto
  • --disable-ssl
  • --disable-lzo
  • --disable-management