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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 repositories... Contain RPMs that...
osg, osg-upcoming are considered production-ready (default).
osg-testing, osg-upcoming-testing have passed developer or integration testing but not acceptance testing
osg-development, osg-upcoming-development have not passed developer, integration or acceptance testing. Do not use without instruction from the OSG Software and Release Team.
osg-contrib have been contributed from outside of the OSG Software and Release Team. See this section for details.


The upcoming repositories contain newer software that might require manual action after an update. They are not enabled by default and must be enabled in addition to the main osg repository. See the upcoming software 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 7, CentOS 7, CentOS Stream 8, Rocky Linux 8, AlmaLinux 8)
    • Server-Extras (RHEL 7)
    • powertools (CentOS Stream 8, Rocky Linux 8, AlmaLinux 8)
    • CodeReady Builder (RHEL 8) or crb (all EL9 variants)
  • 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.

We have placed such software in separate repositories. Their names start with osg-upcoming and have the same structure as our standard repositories, as well as the same guarantees of quality and production-readiness.

There are separate sets of upcoming repositories for each release series. For example, the OSG 23 repos have corresponding 23-upcoming repos. The upcoming repositories are meant to be layered on top of our standard repositories: installing software from the upcoming repositories requires also enabling the standard repositories from the same release.

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 (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 OSG Software to ensure that you are getting the OSG-supported versions.

This plugin is built into Yum on EL8 and EL9 distributions.

  1. Install the Yum priorities package:

    root@host # 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 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 7

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

CentOS Stream 8

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

Rocky Linux 8

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

AlmaLinux 8

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


  • 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.

Rocky Linux 9

  • Ensure that the crb repo in /etc/yum.repos.d/rocky.repo is enabled

AlmaLinux 9

  • Ensure that the crb repo in /etc/yum.repos.d/almalinux-crb.repo is enabled

CentOS Stream 9

  • Ensure that the crb repo in /etc/yum.repos.d/centos.repo is enabled

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 7 (For RHEL 7, CentOS 7, and SL 7)
    root@host # yum install
    ## EPEL 8 (For RHEL 8 and CentOS Stream 8, Rocky Linux 8, AlmaLinux 8)
    root@host # yum install
    ## EPEL 9 (For RHEL 9 and CentOS Stream 9, Rocky Linux 9, AlmaLinux 9)
    root@host # 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 23 EL8:

      root@host # yum install
    • OSG 23 EL9:

      root@host # yum install
    • OSG 3.6 EL7:

      root@host # yum install
    • OSG 3.6 EL8:

      root@host # yum install
    • OSG 3.6 EL9:

      root@host # 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.


Automatic updates for EL8 and EL9 variants are provided in the dnf-automatic RPM, which is not installed by default.

To enable only security related automatic updates:

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

  • On EL8 and EL9 variants, edit /etc/dnf/automatic.conf and set upgrade_type = security

CentOS 7, CentOS Stream 8, and CentOS Stream 9 do 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 EL7 variants, run:

    root@host # service yum-cron stop
  • On EL8 and EL9 variants, run:

    root@host # 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>/el9/development /var/www/html/osg/<OSG_RELEASE>/el7

Replace <OSG_RELEASE> with the OSG release you would like to use (e.g. 23-main) 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.


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