Understanding Container Image Details

Why use images from the Red Hat Ecosystem Catalog?

Mission-critical applications require trusted containers. Container images available from the Red Hat Ecosystem Catalog are built from base images that have been vetted by Red Hat’s internal security team and hardened against security flaws.

What types of container images are listed?

Most container images in the Red Hat Ecosystem Catalog fall into one of these categories:

  • Base container images:

    • Built by Red Hat, base images provide a secure and stable base to build your applications.

  • Intermediate container images:

    • These layered images add tools and libraries to base images, allowing you to develop particular types of applications. Software Collections Images include containers for specific runtime environments, including node.js, perl, ruby, rails, python and php. The .NET Core container images provide the only commercially supported .NET core platform available on Linux for building and running .NET Core applications.

  • Stand Alone container images:

    • These ready-to-run container images provide services or end-user applications that you can execute in your own container environment. Examples are containers for running Apache, MySQL and MariaDB services. Stand alone images also encompass those produced by Independent Software Vendors (ISVs), offering containerized versions of popular commercial applications made to run on Red Hat Enterprise Linux systems.

  • Operator images:

    • Container images that run as OpenShift operators

What does an image identified as a “beta”, “tech preview”, or “deprecated” mean?

An image marked as “tech preview” is not fully supported and is not intended to be used in production. For a detailed explanation of tech preview, see Technology Preview Features Support Scope.

An image identified as a “Beta” image is made available for testing purposes in non-production environments as a pre-release. It does not fall under any existing support agreement.

A “deprecated” repository is one that is expected to be phased out in the future and, therefore, should not be relied upon going forward. the Red Hat Ecosystem Catalog keeps these repositories to prevent builds that rely on them from breaking. When a repository has been deprecated, there will be no further updates of images in that repository.

How can I see a list of all versions of an image inside a repository?

Image versions are indicated by tags. To see the tags associated with an image repository, go to the main page for an image repository and select the Tags tab. If there are multiple versions associated with a repository, they are represented by a list of Tag Names displayed on that page.

What do the different tags mean on the Tag tab?

Many of the images in the Red Hat Ecosystem Catalog have multiple tags associated with them. The tag is the part of the image name that appears at the end of the base image name. If you try to pull an image using the base name alone, with no tag added, it implies that the tag to be used is :latest.

Besides :latest, image tags are typically used to identify the version of the image. For example, the latest container image for RHEL 7.3 could be identified as :7.3-82 (the 82nd iteration of the 7.3 image), :7.3 (the latest 7.3 image available) and :latest (the latest RHEL 7 image available).