Software Channels

Channels are a method of grouping software packages. Software packages are provided by repositories, and repositories are associated with channels. Subscribing a client to a software channel allows the client to install and update any of the software associated with it.

In Uyuni, channels are divided into base channels and child channels. Organizing channels in this way ensures that only compatible packages are installed on each system. A client must be subscribed to only one base channel, assigned during registration based on the client operating system and architecture. For paid channels provided by a vendor, you must have an associated subscription.

A base channel consists of packages built for a specific operating system type, version, and architecture. For example, the SUSE Linux Enterprise Server 15 x86-64 base channel contains only software compatible with that operating system and architecture.

A child channel is associated with a base channel and provides only packages that are compatible with the base channel. A system can be subscribed to multiple child channels of its base channel. When a system has been assigned to a base channel, it is only possible for that system to install the related child channels. For example, if a system has been assigned to the SUSE Linux Enterprise Server 15 x86_64 base channel, they can only install or update packages made available through the compatible base channel, or any of its associated child channels.

In the Uyuni Web UI you can browse your available channels by navigating to Software  Channel List  All. You can modify or create new channels by navigating to Software  Manage  Channels.

For more on using channels, including custom channels, see Channel Management.

Handling the Installer Updates Channel after Bootstrapping

Once a client system has been bootstrapped, the Installer Updates channel should be removed. The standard update channel already includes the necessary updates, making this channel redundant.

Additionally, during migrations, this channel is unnecessary and should not be used.

1. Packages Provided by SUSE Package Hub

SUSE Package Hub is an extension to SUSE Linux Enterprise products that provides additional open source software provided by the openSUSE community.

The packages in SUSE Package Hub are provided by the openSUSE community. They are not supported by SUSE.

If you are using SUSE Linux Enterprise operating systems on your clients, you can enable the SUSE Package Hub extension to access these additional packages. This provides the SUSE Package Hub channels, which you can subscribe your clients to.

SUSE Package Hub provides a large number of packages, which can take a long time to synchronize and consume a large amount of disk space. Do not enable SUSE Package Hub unless you require the packages it provides.

To avoid unintentionally installing or updating unsupported packages, we recommend that you implement a content lifecycle management strategy that initially denies all SUSE Package Hub packages. You can then explicitly enable the specific packages you require. For more information about content lifecycle management, see Content Lifecycle Management.

2. Packages Provided by AppStream

For Red Hat based clients, additional packages are available through AppStream. In most cases, the AppStream packages are required to ensure that you have all the software you need.

3. Packages Provided by EPEL

For Red Hat based clients, additional packages are available through EPEL (extra packages for enterprise Linux). EPEL is an optional package repository that provides additional software.

The packages in EPEL are provided by the Fedora community. They are not supported by SUSE.

If you are using Red Hat operating systems on your clients, you can enable the EPEL extension to access these additional packages. This provides the EPEL channels, which you can subscribe your clients to.

EPEL provides a large number of packages, which can take a long time to synchronize and consume a large amount of disk space. Do not enable the EPEL repositories unless you require the packages it provides.

To avoid unintentionally installing or updating unsupported packages, we recommended that you implement a content lifecycle management (CLM) strategy that initially denies all EPEL packages. You can then explicitly enable the specific packages you require. For more information about content lifecycle management, see Content Lifecycle Management.

4. Unified Installer Updates Channels on SUSE Linux Enterprise Clients

This channel is used by the Unified Installer to ensure it is up to date before it installs the operating system. All SUSE Linux Enterprise products should have access to the installer updates channel during installation.

For SUSE Linux Enterprise Server clients the installer updates channel is synchronized by default when you add a product that contains them, and are enabled when you create an autoinstallable distribution with these product channels.

For all other SUSE Linux Enterprise variants, including SUSE Linux Enterprise for SAP, you must add the installer updates channel manually. To do this, clone the appropriate SUSE Linux Enterprise Server installer updates channel below the base channel of these SUSE Linux Enterprise variants. When creating an autoinstallable distribution for these SUSE Linux Enterprise variants after the channel was cloned, it is used automatically.