OpenShift 4.10 I: Red Hat Official Container Repository/Registry

Installation

>$ sudo dnf install container-tools

Container repositories/registries are configured in.

>$ cat /etc/containers/registries.conf
...
unqualified-search-registries = ["registry.fedoraproject.org", "registry.access.redhat.com", "registry.centos.org", "quay.io", "docker.io"]
...

$ man 5 containers-registries.conf
...
       Container engines will use the $HOME/.config/containers/registries.conf if it exists, otherwise  they
       will use /etc/containers/registries.conf
...
   EXAMPLE
              unqualified-search-registries = ["example.com"]

              [[registry]]
              prefix = "example.com/foo"
              insecure = false
              blocked = false
              location = "internal-registry-for-example.com/bar"

              [[registry.mirror]]
              location = "example-mirror-0.local/mirror-for-foo"

              [[registry.mirror]]
              location = "example-mirror-1.local/mirrors/foo"
              insecure = true

       Given the above, a pull of example.com/foo/image:latest will try:
           1. example-mirror-0.local/mirror-for-foo/image:latest
           2. example-mirror-1.local/mirrors/foo/image:latest
           3. internal-registry-for-example.net/bar/image:latest
...
   EXAMPLE
       The  following  example  configuration  defines  two searchable registries, one insecure registry, and two
       blocked registries.

              [registries.search]
              registries = ['registry1.com', 'registry2.com']

              [registries.insecure]
              registries = ['registry3.com']

              [registries.block]
              registries = ['registry.untrusted.com', 'registry.unsafe.com']
...

$ echo 'unqualified-search-registries = ["registry.redhat.io"]'> /home/student/.config/containers/registries.conf

Browse official Red Hat Container Catalog

https://catalog.redhat.com/

https://catalog.redhat.com/software

https://catalog.redhat.com/software/containers/explore

Home > Software > Container images

Example Apache httpd: https://catalog.redhat.com/software/containers/ubi9/httpd-24/61a60c3e3e9240fca360f74a

>Using Red Hat login
  Registry: registry.redhat.io
  Container: registry.redhat.io/ubi9/httpd-24

Unauthenticated
  Registry: registry.access.redhat.com
  Container: registry.access.redhat.com/ubi9/httpd-24

"Although both registry.access.redhat.com and registry.redhat.io hold essentially the same container images, some images that require a subscription are only available from registry.redhat.io."

https://access.redhat.com/RegistryAuthentication

"Red Hat Quay is a private container registry that stores, builds, and deploys container images."

https://www.redhat.com/en/resources/quay-datasheet