Buildbot no longer supports Python 2.7 on the Buildbot master.
2.2.4. Buildmaster Setup¶
18.104.22.168. Creating a buildmaster¶
As you learned earlier (System Architecture), the buildmaster runs on a central host (usually one that is publicly visible, so everybody can check on the status of the project), and controls all aspects of the buildbot system
You will probably wish to create a separate user account for the buildmaster, perhaps named
Do not run the buildmaster as
You need to choose a directory for the buildmaster, called the
This directory will be owned by the buildmaster.
It will contain configuration, the database, and status information - including logfiles.
On a large buildmaster this directory will see a lot of activity, so it should be on a disk with adequate space and speed.
Once you’ve picked a directory, use the
buildbot create-master command to create the directory and populate it with startup files:
buildbot create-master -r basedir
You will need to create a configuration file before starting the buildmaster.
Most of the rest of this manual is dedicated to explaining how to do this.
A sample configuration file is placed in the working directory, named
master.cfg.sample, which can be copied to
master.cfg and edited to suit your purposes.
(Internal details: This command creates a file named
buildbot.tac that contains all the state necessary to create the buildmaster.
Twisted has a tool called
twistd which can use this .tac file to create and launch a buildmaster instance.
Twistd takes care of logging and daemonization (running the program in the background).
/usr/bin/buildbot is a front end which runs twistd for you.)
Your master will need a database to store the various information about your builds, and its configuration.
By default, the
sqlite3 backend will be used.
This needs no configuration, neither extra software.
All information will be stored in the file
Buildbot however supports multiple backends.
See Using A Database Server for more options.
This section lists options to the
You can also type
buildbot create-master --help for an up-to-the-moment summary.
This option will allow to re-use an existing directory.
This disables internal worker log management mechanism. With this option worker does not override the default logfile name and its behaviour giving a possibility to control those with command-line options of twistd daemon.
This creates a “relocatable”
buildbot.tac, which uses relative paths instead of absolute paths, so that the buildmaster directory can be moved about.
The name of the configuration file to use. This configuration file need not reside in the buildmaster directory.
This is the size in bytes when to rotate the Twisted log files. The default is 10MiB.
This is the number of log rotations to keep around. You can either specify a number or
Noneto keep all
twistd.logfiles around. The default is 10.
The database that the Buildmaster should use. Note that the same value must be added to the configuration file.
22.214.171.124. Upgrading an Existing Buildmaster¶
If you have just installed a new version of the Buildbot code, and you have buildmasters that were created using an older version, you’ll need to upgrade these buildmasters before you can use them. The upgrade process adds and modifies files in the buildmaster’s base directory to make it compatible with the new code.
buildbot upgrade-master basedir
This command will also scan your
master.cfg file for incompatibilities (by loading it and printing any errors or deprecation warnings that occur).
Each buildbot release tries to be compatible with configurations that worked cleanly (i.e. without deprecation warnings) on the previous release: any functions or classes that are to be removed will first be deprecated in a release, to give you a chance to start using the replacement.
upgrade-master command is idempotent.
It is safe to run it multiple times.
After each upgrade of the Buildbot code, you should use
upgrade-master on all your buildmasters.
upgrade-master command may perform database schema modifications.
To avoid any data loss or corruption, it should not be interrupted.
As a safeguard, it ignores all signals except
In general, Buildbot workers and masters can be upgraded independently, although some new features will not be available, depending on the master and worker versions.
Beyond this general information, read all of the sections below that apply to versions through which you are upgrading.
Upgrading from Buildbot-0.8.x to Buildbot-0.9.x¶
See Upgrading to Buildbot 0.9.0 for a guide to upgrading from 0.8.x to 0.9.x
Upgrading a Buildmaster to Buildbot-0.7.6¶
The 0.7.6 release introduced the
public_html/ directory, which contains
index.html and other files served by the
Waterfall status displays.
upgrade-master command will create these files if they do not already exist.
It will not modify existing copies, but it will write a new copy in e.g.
index.html.new if the new version differs from the version that already exists.
Upgrading a Buildmaster to Buildbot-0.8.0¶
Buildbot-0.8.0 introduces a database backend, which is SQLite by default.
upgrade-master command will automatically create and populate this database with the changes the buildmaster has seen.
Note that, as of this release, build history is not contained in the database, and is thus not migrated.
Upgrading into a non-SQLite database¶
If you are not using sqlite, you will need to add an entry into your
master.cfg to reflect the database version you are using.
The upgrade process does not edit your
master.cfg for you.
So something like:
# for using mysql: c['db_url'] = 'mysql://bbuser:<password>@localhost/buildbot'
Once the parameter has been added, invoke
This will extract the DB url from your configuration file.
See Database Specification for more options to specify a database.