Using the Cluster Samples Operator with an alternate registry | Images

About the mirror registry
- Preparing the mirror host
- Installing the OpenShift CLI
Configuring credentials that allow images to be mirrored
Mirroring the OKD image repository
Using Cluster Samples Operator image streams with alternate or mirrored registries
- Cluster Samples Operator assistance for mirroring

You can use the Cluster Samples Operator with an alternate registry by first creating a mirror registry.

You must have access to the internet to obtain the necessary container images. In this procedure, you place the mirror registry on a mirror host that has access to both your network and the internet.

About the mirror registry

You can mirror the images that are required for OKD installation and subsequent product updates to a container mirror registry such as Red Hat Quay, JFrog Artifactory, Sonatype Nexus Repository, or Harbor. If you do not have access to a large-scale container registry, you can use the mirror registry for Red Hat OpenShift, a small-scale container registry included with OKD subscriptions.

You can use any container registry that supports Docker v2-2, such as Red Hat Quay, the mirror registry for Red Hat OpenShift, Artifactory, Sonatype Nexus Repository, or Harbor. Regardless of your chosen registry, the procedure to mirror content from Red Hat hosted sites on the internet to an isolated image registry is the same. After you mirror the content, you configure each cluster to retrieve this content from your mirror registry.

The OpenShift image registry cannot be used as the target registry because it does not support pushing without a tag, which is required during the mirroring process.

If choosing a container registry that is not the mirror registry for Red Hat OpenShift, it must be reachable by every machine in the clusters that you provision. If the registry is unreachable, installation, updating, or normal operations such as workload relocation might fail. For that reason, you must run mirror registries in a highly available way, and the mirror registries must at least match the production availability of your OKD clusters.

When you populate your mirror registry with OKD images, you can follow two scenarios. If you have a host that can access both the internet and your mirror registry, but not your cluster nodes, you can directly mirror the content from that machine. This process is referred to as connected mirroring. If you have no such host, you must mirror the images to a file system and then bring that host or removable media into your restricted environment. This process is referred to as disconnected mirroring.

For mirrored registries, to view the source of pulled images, you must review the Trying to access log entry in the CRI-O logs. Other methods to view the image pull source, such as using the crictl images command on a node, show the non-mirrored image name, even though the image is pulled from the mirrored location.

Red Hat does not test third party registries with OKD.

Additional information

For information on viewing the CRI-O logs to view the image source, see Viewing the image pull source.

Preparing the mirror host

Before you create the mirror registry, you must prepare the mirror host.

Installing the OpenShift CLI

You can install the OpenShift CLI (oc) to interact with OKD from a command-line interface. You can install oc on Linux, Windows, or macOS.

If you installed an earlier version of oc, you cannot use it to complete all of the commands in OKD 4.17. Download and install the new version of oc.

Installing the OpenShift CLI on Linux

You can install the OpenShift CLI (oc) binary on Linux by using the following procedure.

Procedure

Navigate to https://mirror.openshift.com/pub/openshift-v4/clients/oc/latest/ and choose the folder for your operating system and architecture.
Download oc.tar.gz.
Unpack the archive:
```
$ tar xvf <file>
```
Place the oc binary in a directory that is on your PATH.

To check your PATH, execute the following command:
```
$ echo $PATH
```

Verification

After you install the OpenShift CLI, it is available using the oc command:
```
$ oc <command>
```

Installing the OpenShift CLI on Windows

You can install the OpenShift CLI (oc) binary on Windows by using the following procedure.

Procedure

Navigate to https://mirror.openshift.com/pub/openshift-v4/clients/oc/latest/ and choose the folder for your operating system and architecture.
Download oc.zip.
Unzip the archive with a ZIP program.
Move the oc binary to a directory that is on your PATH.

To check your PATH, open the command prompt and execute the following command:
```
C:\> path
```

Verification

After you install the OpenShift CLI, it is available using the oc command:
```
C:\> oc <command>
```

Installing the OpenShift CLI on macOS

You can install the OpenShift CLI (oc) binary on macOS by using the following procedure.

Procedure

Navigate to https://mirror.openshift.com/pub/openshift-v4/clients/oc/latest/ and choose the folder for your operating system and architecture.
Download oc.tar.gz.
Unpack and unzip the archive.
Move the oc binary to a directory on your PATH.

To check your PATH, open a terminal and execute the following command:
```
$ echo $PATH
```

Verification

Verify your installation by using an oc command:
```
$ oc <command>
```

Configuring credentials that allow images to be mirrored

Create a container image registry credentials file that enables you to mirror images from Red Hat to your mirror.

Prerequisites

You configured a mirror registry to use in your disconnected environment.

Procedure

Complete the following steps on the installation host:

Generate the base64-encoded user name and password or token for your mirror registry by running the following command:
```
$ echo -n '<user_name>:<password>' | base64 -w0 (1)
```
1 For <user_name> and <password>, specify the user name and password that you configured for your registry.
Example output
```
BGVtbYk3ZHAtqXs=
```

Create a .json file and add a section that describes your registry to it:

{
  "auths": {
    "<mirror_registry>": { (1)
      "auth": "<credentials>", (2)
      "email": "you@example.com"
    }
  }
}

1	Specify the registry domain name, and optionally the port, that your mirror registry uses to serve content. For example, `registry.example.com` or `registry.example.com:8443`
2	Specify the base64-encoded user name and password for the mirror registry.

Mirroring the OKD image repository

Mirror the OKD image repository to your registry to use during cluster installation or upgrade.

Prerequisites

Your mirror host has access to the internet.
You configured a mirror registry to use in your restricted network and can access the certificate and credentials that you configured.
You have created a pull secret for your mirror repository.
If you use self-signed certificates, you have specified a Subject Alternative Name in the certificates.

Procedure

Complete the following steps on the mirror host:

Review the OKD downloads page to determine the version of OKD that you want to install and determine the corresponding tag on the Repository Tags page.
Set the required environment variables:
1. Export the release version:
  $ OCP_RELEASE=<release_version>
  For <release_version>, specify the tag that corresponds to the version of OKD to install, such as 4.5.4.
2. Export the local registry name and host port:
  $ LOCAL_REGISTRY='<local_registry_host_name>:<local_registry_host_port>'
  For <local_registry_host_name>, specify the registry domain name for your mirror repository, and for <local_registry_host_port>, specify the port that it serves content on.
3. Export the local repository name:
  $ LOCAL_REPOSITORY='<local_repository_name>'
  For <local_repository_name>, specify the name of the repository to create in your registry, such as ocp4/openshift4.
4. Export the name of the repository to mirror:
  $ PRODUCT_REPO='openshift'
5. Export the path to your registry pull secret:
  $ LOCAL_SECRET_JSON='<path_to_pull_secret>'
  For <path_to_pull_secret>, specify the absolute path to and file name of the pull secret for your mirror registry that you created.
6. Export the release mirror:
  $ RELEASE_NAME="okd"
7. Export the path to the directory to host the mirrored images:
  $ REMOVABLE_MEDIA_PATH=<path> (1)
  1 Specify the full path, including the initial forward slash (/) character.

Mirror the version images to the mirror registry:

If your mirror host does not have internet access, take the following actions:

Connect the removable media to a system that is connected to the internet.

Review the images and configuration manifests to mirror:

$ oc adm release mirror -a ${LOCAL_SECRET_JSON}  \
     --from=quay.io/${PRODUCT_REPO}/${RELEASE_NAME}:${OCP_RELEASE} \
     --to=${LOCAL_REGISTRY}/${LOCAL_REPOSITORY} \
     --to-release-image=${LOCAL_REGISTRY}/${LOCAL_REPOSITORY}:${OCP_RELEASE} --dry-run

Record the entire imageContentSources section from the output of the previous command. The information about your mirrors is unique to your mirrored repository, and you must add the imageContentSources section to the install-config.yaml file during installation.

Mirror the images to a directory on the removable media:

$ oc adm release mirror -a ${LOCAL_SECRET_JSON} --to-dir=${REMOVABLE_MEDIA_PATH}/mirror quay.io/${PRODUCT_REPO}/${RELEASE_NAME}:${OCP_RELEASE}

Take the media to the restricted network environment and upload the images to the local container registry.

$ oc image mirror -a ${LOCAL_SECRET_JSON} --from-dir=${REMOVABLE_MEDIA_PATH}/mirror "file://openshift/release:${OCP_RELEASE}*" ${LOCAL_REGISTRY}/${LOCAL_REPOSITORY} (1)

1	For `REMOVABLE_MEDIA_PATH`, you must use the same path that you specified when you mirrored the images.

Running oc image mirror might result in the following error: error: unable to retrieve source image. This error occurs when image indexes include references to images that no longer exist on the image registry. Image indexes might retain older references to allow users running those images an upgrade path to newer points on the upgrade graph. As a temporary workaround, you can use the --skip-missing option to bypass the error and continue downloading the image index. For more information, see Service Mesh Operator mirroring failed.

If the local container registry is connected to the mirror host, take the following actions:
1. Directly push the release images to the local registry by using following command:
  $ oc adm release mirror -a ${LOCAL_SECRET_JSON} \ --from=quay.io/${PRODUCT_REPO}/${RELEASE_NAME}:${OCP_RELEASE} \ --to=${LOCAL_REGISTRY}/${LOCAL_REPOSITORY} \ --to-release-image=${LOCAL_REGISTRY}/${LOCAL_REPOSITORY}:${OCP_RELEASE}
  This command pulls the release information as a digest, and its output includes the imageContentSources data that you require when you install your cluster.
2. Record the entire imageContentSources section from the output of the previous command. The information about your mirrors is unique to your mirrored repository, and you must add the imageContentSources section to the install-config.yaml file during installation.
  
  The image name gets patched to Quay.io during the mirroring process, and the podman images will show Quay.io in the registry on the bootstrap virtual machine.

To create the installation program that is based on the content that you mirrored, extract it and pin it to the release:

If your mirror host does not have internet access, run the following command:

$ oc adm release extract -a ${LOCAL_SECRET_JSON} --icsp-file=<file> --command=openshift-install "${LOCAL_REGISTRY}/${LOCAL_REPOSITORY}:${OCP_RELEASE}-${ARCHITECTURE}" \
--insecure=true (1)

1	Optional: If you do not want to configure trust for the target registry, add the `--insecure=true` flag.

If the local container registry is connected to the mirror host, run the following command:

$ oc adm release extract -a ${LOCAL_SECRET_JSON} --command=openshift-install "${LOCAL_REGISTRY}/${LOCAL_REPOSITORY}:${OCP_RELEASE}"

To ensure that you use the correct images for the version of OKD that you selected, you must extract the installation program from the mirrored content.

You must perform this step on a machine with an active internet connection.

For clusters using installer-provisioned infrastructure, run the following command:
```
$ openshift-install
```

Using Cluster Samples Operator image streams with alternate or mirrored registries

Most image streams in the openshift namespace managed by the Cluster Samples Operator point to images located in the Red Hat registry at registry.redhat.io.

The cli, installer, must-gather, and tests image streams, while part of the install payload, are not managed by the Cluster Samples Operator. These are not addressed in this procedure.

The Cluster Samples Operator must be set to Managed in a disconnected environment. To install the image streams, you have a mirrored registry.

Prerequisites

Access to the cluster as a user with the cluster-admin role.
Create a pull secret for your mirror registry.

Procedure

Access the images of a specific image stream to mirror, for example:

$ oc get is <imagestream> -n openshift -o json | jq .spec.tags[].from.name | grep registry.redhat.io

Mirror images from registry.redhat.io associated with any image streams you need

$ oc image mirror registry.redhat.io/rhscl/ruby-25-rhel7:latest ${MIRROR_ADDR}/rhscl/ruby-25-rhel7:latest

Create the cluster’s image configuration object:

$ oc create configmap registry-config --from-file=${MIRROR_ADDR_HOSTNAME}..5000=$path/ca.crt -n openshift-config

Add the required trusted CAs for the mirror in the cluster’s image configuration object:

$ oc patch image.config.openshift.io/cluster --patch '{"spec":{"additionalTrustedCA":{"name":"registry-config"}}}' --type=merge

Update the samplesRegistry field in the Cluster Samples Operator configuration object to contain the hostname portion of the mirror location defined in the mirror configuration:
```
$ oc edit configs.samples.operator.openshift.io -n openshift-cluster-samples-operator
```
This is required because the image stream import process does not use the mirror or search mechanism at this time.
Add any image streams that are not mirrored into the skippedImagestreams field of the Cluster Samples Operator configuration object. Or if you do not want to support any of the sample image streams, set the Cluster Samples Operator to Removed in the Cluster Samples Operator configuration object.

The Cluster Samples Operator issues alerts if image stream imports are failing but the Cluster Samples Operator is either periodically retrying or does not appear to be retrying them.

Many of the templates in the openshift namespace reference the image streams. So using Removed to purge both the image streams and templates will eliminate the possibility of attempts to use them if they are not functional because of any missing image streams.

Cluster Samples Operator assistance for mirroring

During installation, OKD creates a config map named imagestreamtag-to-image in the openshift-cluster-samples-operator namespace. The imagestreamtag-to-image config map contains an entry, the populating image, for each image stream tag.

The format of the key for each entry in the data field in the config map is <image_stream_name>_<image_stream_tag_name>.

During a disconnected installation of OKD, the status of the Cluster Samples Operator is set to Removed. If you choose to change it to Managed, it installs samples.

The use of samples in a network-restricted or discontinued environment may require access to services external to your network. Some example services include: Github, Maven Central, npm, RubyGems, PyPi and others. There might be additional steps to take that allow the cluster samples operators’s objects to reach the services they require.

You can use this config map as a reference for which images need to be mirrored for your image streams to import.

While the Cluster Samples Operator is set to Removed, you can create your mirrored registry, or determine which existing mirrored registry you want to use.
Mirror the samples you want to the mirrored registry using the new config map as your guide.
Add any of the image streams you did not mirror to the skippedImagestreams list of the Cluster Samples Operator configuration object.
Set samplesRegistry of the Cluster Samples Operator configuration object to the mirrored registry.
Then set the Cluster Samples Operator to Managed to install the image streams you have mirrored.

See Using Cluster Samples Operator image streams with alternate or mirrored registries for a detailed procedure.