GroupServer installation

Authors:Michael JasonSmith; Richard Waid; Marek Kuziel; Alice Rose; Dan Randow
Contact:Michael JasonSmith <>
Date:2016-03-03 (see History)
Copyright:This document is licensed under a Creative Commons Attribution-Share Alike 4.0 International License by

Installation can be tricky: much has to be configured and set up correctly or installation will fail. We wrote this documentation for people with moderate experience in Linux system administration. If you get stuck, please ask us questions in GroupServer Development. Other more detailed guides would be gratefully accepted.


GroupServer is developed on Ubuntu, and is know to run on CentOS. We will gladly accept any modifications you have that will make GroupServer run on more platforms.

Quick start

  1. Download the latest version of GroupServer from <> and extract the archive.

  2. Create a new hostname for your GroupServer site. Yes, you will need a new one (see Pick a Host Name).

  3. Edit config.cfg (see Configure GroupServer).

  4. Enable prepared transaction support in PostgreSQL (see Configure PostgreSQL).

  5. Run the following (see Run the installer):

    $ ./
  6. Start Zope:

    $ ./bin/instance fg
  7. Visit your new site.

  8. Commence the next steps.

Set up

GroupServer builds on five major infrastructure packages. These packages are installed by the installation script. However, you must configure the relationship between GroupServer and to these packages before you run the installer.

  • Postfix handles both the incoming and outgoing email.
  • Zope provides the web framework and basic web server support.
  • PostgreSQL stores the posts.
  • ZODB stores some web content and the user-information.
  • Redis provides an application cache.
The architecture of GroupServer

GroupServer listens for connections on a single port (8080, by default) and serves up either the administration interface (ZMI) or the normal web interface depending on the name used to connect to the web server (virtual hosting). Email comes into the server via the web interface, and goes out using SMTP. The data is stored in a variety of locations.

Setting up GroupServer is done in four steps: first pick a host name, then configure GroupServer, run the installer to install the system, and finally start Zope.

Pick a host name

Your new site needs its own hostname. This is the name that people will use to access your new GroupServer site with a web browser. For a trial system, the name can be set up in the hosts(5) file.

  1. Edit /etc/hosts as the root user.

  2. Add the new host name to the localhost entry, which is normally the first one. For example, to add the name gstest change the line to the following:    localhost gstest
  3. Save the /etc/hosts file.

Configure GroupServer

The configuration of GroupServer is mostly carried out by modifying the config.cfg file, which is located in the root of the GroupServer folder [1]. First you must configure the GroupServer Site itself. Next the Zope system, which will run your GroupServer site, needs to be configured, before the database storage.

GroupServer site

You will need to check all the configuration for your initial site.

The domain name used by people accessing your new GroupServer site. It must be the same as what you picked a host name earlier (see Pick a host name).
When GroupServer is installed, an example site and group are created. So you can use the administration functions you must sign in as an administrator. This is the email address of that administrator. Posts to the example group will be sent to the administrator at this address. This email address must work.
The password of the administrator of the new GroupServer site. The password will be used to sign in, and can be changed after the site has been created.
support_email The email address where support messages are
sent, and were email notifications are send from. For testing this can be set to your own or the admin email address.
The SMTP host that will be used to send email from GroupServer. It defaults to localhost, assuming you will be running Postfix on the same machine as GroupServer.


Zope is used to provide the web-framework for GroupServer, and a basic web-server. The server listens for connections on a single port (the zope_port) and provides the GroupServer UI if connections are made using the host name, or the Zope Management Interface (ZMI) if connections are made with any other host names.

The zope_host and zope_port are probably correct for most systems, weather you are testing or if you are going to proxy GroupServer (see Configuring a web proxy). However, for security we recommend you change the name and password of the Zope administrator.

The name of the host that will run Zope. It defaults to the local machine (
The IP port that Zope will listen to. It defaults to 8080, and it recommended that you leave this value as-is, unless another service is running on port 8080. (Zope will have to run as root to use port 80, and this is discouraged; to use port 80 you will need to proxy GroupServer, see Configuring a web proxy.)
The name of the user who will administer Zope. This is used to log into the Zope Management Interface (ZMI).
The password for the Zope administrator. It can (and should) be changed after GroupServer has been set up.


The IP-address of the zope_host and host (see GroupServer site) must be the same.

Database storage

GroupServer stores most of its data in PostgreSQL. Two passwords need to be set by you to protect this data.

The password required to attach to the PostgreSQL database. The install system will create a PostgreSQL database, and protect it with this pgsql_password.
The RelStorage system will store data in a PostgreSQL database for Zope. This data is protected by the relstorage_password.

Configure PostgreSQL

The RelStorage system that is used by GroupServer requires prepared transaction support to be enabled in PostgreSQL. To enable prepared transaction support carry out the following steps.

  1. Edit the PostgreSQL configuration file. On Ubuntu you must be root to edit this file, which is located in /etc/postgresql/9.x/main/postgresql.conf. (The actual directory name may be different depending on the version of PostgreSQL you have installed; change the 9.{x} to match your version as appropriate.)

  2. Find the line that reads

    max_prepared_transactions = 0

    If the line is set to something other than 0 then nothing needs to change, and you can run the installer.

  3. Change the line to read

    max_prepared_transactions = 1
  4. Restart PostgreSQL. On Ubuntu this is done using the following command:

    $ sudo service postgresql restart

Run the installer

The installer for Ubuntu is a Bash script. (For CentOS and RHEL you will have to carry out the steps by hand.) To run the GroupServer installer enter the following command:

$ ./

You will be prompted for your password. This is required to check that your Ubuntu system has met all the dependencies. Next the installer ensures that the set up is correct.

Permissions:GroupServer can only be run by users with normal privileges. If the installation directory is owned by root then you must change the ownership of the installation directory to a normal user and switch (su) to that user. Then run the installer.

The rest of the installation process should be completely automatic.

  • The system will create a sandbox for your GroupServer site, with its own version of Python, placed in ./bin/.

  • It will then configure the PostgreSQL databases that store the data for your site.

  • Finally, it will start the buildout [2] system that will download and install all the requirements for GroupServer (around 47MB of packages) including:

    You need a functioning network connection to download the GroupServer requirements.

It is a good idea to make a cup of coffee, or go to lunch, while buildout processes. The log file for the install will be written to parts/log/{year}-{month}-{day}.{n}.log.


If a file partly downloads and the network connection times out then you may see a CRC-check error after you restart the install. For example:

Getting distribution for 'sqlalchemy==0.9.10'.
error: CRC check failed 0xcea84515 != 0x22d9d947L

To recover from this error, delete the associated file in downloads/dist and restart the build.

CentOS and RHEL

The process to install GroupServer on CentOS or RedHat Enterprise Linux is manual. The basic idea is as follows, but it lacks testing.


Commands that have to be run as root are shown on lines that begin with a #. Commands that must be run as a normal user are shown on lines that begin with a $.

  1. Install the Dependencies.

    PostgreSQL:The version of PostgreSQL that is supplied with RHEL 6.x and CentOS 6.x (PostgreSQL 8.4) lacks the features required by GroupServer. You will need to install PostgreSQL 9, including the development libraries using the instruction provided by the PostgreSQL project.
    Python:The version of Python supplied with RHEL 6.x and CentOS 6.x (Python 2.6) lack the features required by GroupServer. You will need to install Python 2.7 using these instructions from H₂
  2. Create the two database users specified in config.cfg, using createuser:

    # createuser -D -S -R -l gsadmin
    # createuser -D -S -R -l gszodbadmin
  3. Change the PostgreSQL authentication from ident to md5.

    1. Open the file pg_hba.conf. (It is normally found within /etc/postgresql, but the specific location depends on your version of PostgreSQL.)

    2. Change ident to md5 in the lines that read:

      host  all  all  ident
      host  all  all  ::1/128       ident

      They should end up like the following:

      host  all  all  md5
      host  all  all  ::1/128       md5
    3. Restart PostgreSQL.

  4. Create the two databases specified in config.cfg using createdb:

    # createdb -Ttemplate0 -O gsadmin -EUTF-8 groupserver
    # createdb -Ttemplate0 -O gszodbadmin -EUTF-8 groupserverzodb
  5. Get the Python virtualenv package:

    # easy_install virtualenv
  6. Set up a Python virtual-environment for GroupServer:

    $ virtualenv --python=python2.7 --no-site-packages .
  7. Activate the Python virtual-environment (note the dot-space at the start of the command):

    $ . bin/activate
  8. Install the argparse module:

    $ pip install argparse==1.1
  9. Fetch the zc.buildout system that builds GroupServer:

    $ pip install zc.buildout==2.3.1
  10. Update setuptools:

    $ pip install setuptools==18.0.1
  11. Bootstrap the installation:

    $ buildout bootstrap
  12. Install the dependencies, which will take at least seven minutes:

    $ buildout install
  13. Create your site:

    $ buildout -c site.cfg install

Start Zope

Your GroupServer site is supported by Zope. To start Zope run the following command:

$ ./bin/instance fg

Zope will have started when the message Zope Ready to handle requests is displayed in the terminal.

You should be able to view your GroupServer site at http://{host}:{zope_port}. If you kept the defaults, the address will be <http://gstest:8080>.

Use Control-c to stop Zope.

Next steps


Version Date Change
16.04 2016-04-05 Adding instructions for changing the authentication used by PostgreSQL in CentOS and RHEL
16.04 2016-03-03 Determining that Pastis will be GroupServer 16.04
16.04 2015-12-16 Updating the CentOS and RHEL documentation, following the changes to the configuration files.
15.11 2015-08-17 Updating the Sphinx markup, and mentioning the log files.
15.03 2015-03-27 Updating the CentOS install instructions.
15.03 2015-03-25 Making a note about PostgreSQL 9 on CentOS and RHEL.
15.03 2015-03-06 Moving the Dependencies and Download sections to Getting GroupServer.
14.11 2014-11-17 Renaming the Requirements section Dependencies.
14.11 2014-10-30 Moving the Remove GroupServer section to Remove GroupServer.
14.11 2014-10-30 Integrating updates and suggestions from Scott Fosseen.
14.11 2014-10-21 Adding the setup diagram.
14.11 2014-10-14 Reducing the number of ports to one.
14.06 2014-06-23 Moving the sections for configuring the proxy and Postfix to their own documents.
14.03 2014-03-25 Clarifying the Requirements wording.
14.03 2014-03-20 Updating to Ouzo.
12.11 2012-11-27 Adding the sections CentOS and RHEL and Configure PostgreSQL.
12.11 2012-11-19 Adding a link to the Postfix documentation for Ubuntu.
12.11 2012-10-25 Removing some odd dependencies.
12.05 2012-04-30 Updating the Configure GroupServer and Run the Installer sections.
12.05 2012-04-24 Removing unnecessary dependencies, and using pip in the Run Buildout section.
11.08 2011-12-19 Adding the packages required for XML support and XSLT support on RHEL and CentOS to the list of Requirements.
11.08 2011-12-16 Adding the CentOS packages to the list of Requirements, with much thanks to Patrick Leckey.
11.08 2011-11-15 Altering the requirements to switch the build-essential dependency to make on the advice of David Sturman.
11.08 2011-10-27 Adding the Download section, and clarifying some more of the documentation.
11.08 2011-10-26 Correcting some mistakes, and clarifying the documentation on the advice of Ross Chesley
11.08 2011-09-01 Reordering the subsections of Configure Zope.
11.07 2011-07-08 Adding the build-essential dependency and the cut-n-paste apt-get block to the Requirements.
11.06 2011-07-05 Adding the prologue.
11.06 2011-07-04 Updating the notes, because of a change to the name of the initial GroupServer instance.
11.06 2011-06-17 Added postfix configuration and spooling notes.
11.05 2011-05-26 Fixing a typing mistake, and mentioned that the pgsql_dbname and pgsql_user had to be different.
10.09 2010-09-01 Changing how the configuration options are set.
1.0β² 2010-07-15 Improving the buildout instructions.
1.0β² 2010-07-07 Changing the Zope 2.10 (Python 2.4) instructions to Zope 2.13 (Python 2.6) instructions.
1.0β 2010-06-04 Removed a duplicated instruction from the Quick Start, and bumped the version number.
1.0α 2010-05-31 Fixing a typo and adding minor improvements.
1.0α 2010-05-01 Fixing, because upstream broke our buildout.
1.0α 2010-04-29 Better automatic configuration, so the Configure GroupServer section has been removed.
1.0α 2010-04-28 Improving the documentation for gs_port and added documentation for the gs_admin and gs_user configuration options.
1.0α 2010-04-23 Adding a link to the downloads page. Clarified the security changes that are made to PostgreSQL.
1.0α 2010-04-06 Fixing some quoting in the requirements.
1.0α 2010-03-31 Fixing the Requirements, adding Remove GroupServer and History.
1.0α 2010-03-25 Fixing the config options, added Quick Start.
1.0α 2009-10-04 Updating to reflect the new egg-based system.
[1]The cfg files are interpreted by the standard Python ConfigParser module, which accepts a syntax very similar to Windows INI files.
[2]For more on buildout see Buildout and the Buildout site.