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OSG Yum Repositories

This document introduces Yum repositories and how they are used in the OSG. If you are unfamiliar with Yum, see the documentation on using Yum and RPM.


The OSG hosts multiple repositories at that are intended for public use:

The OSG Yum repository... Contains RPMs that...
osg are considered production-ready (default).
osg-rolling are considered production-ready but are released at faster pace than the osg repository.
osg-testing have passed developer or integration testing but not acceptance testing
osg-development have not passed developer, integration or acceptance testing. Do not use without instruction from the OSG Software and Release Team.
osg-upcoming, osg-upcoming-rolling, osg-upcoming-testing, osg-upcoming-development have newer versions that may require manual action after an update. See this section for details.
osg-contrib have been contributed from outside of the OSG Software and Release Team. See this section for details.

OSG's RPM packages also rely on external packages provided by supported OSes and EPEL. You must have the following repositories available and enabled:

  • OS repositories, including the following ones that aren't enabled by default:
    • extras (SL 6/7, CentOS 6/7/8)
    • Server-Extras (RHEL 6/7)
    • PowerTools (CentOS 8)
    • CodeReady Builder (RHEL 8)
  • EPEL repositories
  • OSG repositories

If any of these repositories are missing, you may end up with installation issues or missing dependencies.


Other repositories, such as jpackage, dag, or rpmforge, are not supported and you may encounter problems if you use them.

Upcoming Software

Certain sites have requested new versions of software that would be considered "disruptive" or "experimental": upgrading to them would likely require manual intervention after their installation. We do not want sites to unwittingly upgrade to these versions. For the benefit of the sites that are interested in upgrading to these versions, we want to provide the same assurance of quality and production-readiness that we guarantee for the osg release repository.

Due to the relatively small number of such packages, a full fork of the OSG 3 distribution is not warranted. Instead, we have created a separate set of repositories that contain only the "disruptive" versions of the software.

These repositories have the same structure as our standard repositories. For example, there are osg-upcoming-testing and osg-upcoming repositories, which are analagous to the osg-testing and osg repositories, respectively.

A full installation of our software stack is not possible using only the osg-upcoming repositories, since they contain a small subset of the software we ship. Both the main osg and the osg-upcoming repositories will need to be enabled for the installation to work. Because of this, interoperability will be maintained between the main osg and osg-upcoming.

Depending on test results from sites, some packages in osg-upcoming may eventually end up in the main osg branch. The rest of the packages will eventually form the basis of the next OSG release series (e.g. "OSG 3.5").

Contrib Software

In addition to our regular software repositories, we also have a contrib (short for "contributed") software repository. This is software that is does not go through the same software testing and release processes as the official OSG Software release, but may be useful to you. Particularly, contrib software is not guaranteed to be compatible with the rest of the OSG Software stack nor is it supported by the OSG.

The definitive list of software in the contrib repository can be found here:

If you would like to distribute your software in the OSG contrib repository, please contact us with a description of your software, what users it serves, and relevant RPM packaging.

Installing Yum Repositories

Install the Yum priorities plugin (EL6, EL7)

The Yum priorities plugin is used to tell Yum to prefer OSG packages over EPEL or OS packages. It is important to install and enable the Yum priorities plugin before installing grid software to ensure that you are getting the OSG-supported versions.

This plugin is built into Yum on EL8 distributions.

  1. Install the Yum priorities package:

    [email protected] # yum install yum-plugin-priorities
  2. Ensure that /etc/yum.conf has the following line in the [main] section:


Enable additional OS repositories

Some packages depend on packages that are in OS repositories not enabled by default. The repositories to enable, as well as the instructions to enable them, are OS-dependent.


A repository is enabled if it has enabled=1 in its definition, or if the enabled line is missing (i.e. it is enabled unless specified otherwise.)

SL 6 and 7

  • Install the yum-conf-extras RPM package.
  • Ensure that the sl-extras repo in /etc/yum.repos.d/sl-extras.repo is enabled.

CentOS 6 and 7

  • Ensure that the extras repo in /etc/yum.repos.d/CentOS-Base.repo is enabled.

CentOS 8

  • Ensure that the extras repo in /etc/yum.repos.d/CentOS-Extras.repo is enabled.
  • Ensure that the PowerTools repo in /etc/yum.repos.d/CentOS-PowerTools.repo is enabled.

RHEL 6 and 7

  • Ensure that the Server-Extras channel is enabled.


  • Ensure that the CodeReady Linux Builder channel is enabled. See Red Hat's instructions on how to enable this repo.

Install the EPEL repositories

OSG software depends on packages distributed via the EPEL repositories. You must install and enable these first.

  • Install the EPEL repository, if not already present. Choose the right version to match your OS version.

    ## EPEL 6 (For RHEL 6, CentOS 6, and SL 6)
    [email protected] # yum install
    ## EPEL 7 (For RHEL 7, CentOS 7, and SL 7)
    [email protected] # yum install
    ## EPEL 8 (For RHEL 8 and CentOS 8)
    [email protected] # yum install
  • Verify that /etc/yum.repos.d/epel.repo exists; the [epel] section should contain:

    • The line enabled=1

    • Either no priority setting, or a priority setting that is 99 or higher


If you have your own mirror or configuration of the EPEL repository, you MUST verify that the priority of the EPEL repository is either missing, or 99 or a higher number. The OSG repositories must have a better (numerically lower) priority than the EPEL repositories; otherwise, you might have dependency resolution ("depsolving") issues.

Install the OSG Repositories

This document assumes a fresh install. For instructions on upgrading from one OSG series to another, see the release series document.

  1. Install the OSG repository for your OS version and the OSG release series that you wish to use:

    • OSG 3.5 EL8:

      [email protected] # yum install
    • OSG 3.5 EL7:

      [email protected] # yum install
    • OSG 3.4 EL7:

      [email protected] # yum install
    • OSG 3.4 EL6:

      [email protected] # yum install
  2. The only OSG repository enabled by default is the release one. If you want to enable another one (e.g. osg-testing), then edit its file (e.g. /etc/yum.repos.d/osg-testing.repo) and change the enabled option from 0 to 1:

    name=OSG Software for Enterprise Linux 7 - Testing - $basearch

Optional Configuration

Enable automatic security updates

For production services, we suggest only changing software versions during controlled downtime. Therefore we recommend security-only automatic updates or disabling automatic updates entirely.


RHEL/CentOS 8 automatic updates are provided in the dnf-automatic RPM, which is not installed by default.

To enable only security related automatic updates:

  • On RHEL 6/SL 6, edit /etc/sysconfig/yum-autoupdate and set USE_YUMSEC="true"

  • On RHEL 7/SL 7, edit /etc/yum/yum-cron.conf and set update_cmd = security

  • On RHEL 8, edit /etc/dnf/automatic.conf and set upgrade_type = security

CentOS 6/7/8 does not support security-only automatic updates; doing any of the above steps will prevent automatic updates from happening at all.

To disable automatic updates entirely:

  • On EL6, edit /etc/sysconfig/yum-autoupdate and set ENABLED="false"

  • On EL7, run:

    [email protected] # service yum-cron stop
  • On EL8, run:

    [email protected] # systemctl disable --now dnf-automatic.timer

Configuring Spacewalk priorities

Sites using Spacewalk to manage RPM packages will need to configure OSG Yum repository priorities using their Spacewalk ID. For example, if the OSG 3.4 repository's Spacewalk ID is centos_7_osg34_dev, modify /etc/yum/pluginconf.d/90-osg.conf to include the following:

priority = 98

Repository Mirrors

If you run a large site (>20 nodes), you should consider setting up a local mirror for the OSG repositories. A local Yum mirror allows you to reduce the amount of external bandwidth used when updating or installing packages.

Add the following to a file in /etc/cron.d:

<RANDOM> * * * * root rsync -aH rsync:// /var/www/html/osg/

Or, to mirror only a single repository:

<RANDOM> * * * * root rsync -aH rsync://<OSG_RELEASE>/el6/development /var/www/html/osg/<OSG_RELEASE>/el6

Replace <OSG_RELEASE> with the OSG release you would like to use (e.g. 3.4) and <RANDOM> with a number between 0 and 59.

On your worker node, you can replace the baseurl line of /etc/yum.repos.d/osg.repo with the appropriate URL for your mirror.

If you are interested in having your mirror be part of the OSG's default set of mirrors, please file a support ticket.