Mirroring images for a disconnected installation

Mirroring images for a disconnected installation

You can ensure your clusters only use container images that satisfy your organizational controls on external content. Before you install a cluster on infrastructure that you provision in a restricted network, you must mirror the required container images into that environment. To mirror container images, you must have a registry for mirroring.

You must have access to the internet to obtain the necessary container images. In this procedure, you place your mirror registry on a mirror host that has access to both your network and the internet. If you do not have access to a mirror host, use the Mirroring Operator catalogs for use with disconnected clusters procedure to copy images to a device you can move across network boundaries with.

Prerequisites

You must have a container image registry that supports Docker v2-2 in the location that will host the OKD cluster, such as one of the following registries:

If you have an entitlement to Red Hat Quay, see the documentation on deploying Red Hat Quay for proof-of-concept purposes or by using the Quay Operator. If you need additional assistance selecting and installing a registry, contact your sales representative or Red Hat support.

If you do not already have an existing solution for a container image registry, subscribers of OKD are provided a mirror registry for Red Hat OpenShift. The mirror registry for Red Hat OpenShift is included with your subscription and is a small-scale container registry that can be used to mirror the required container images of OKD in disconnected installations.

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 about viewing the CRI-O logs to view the image source, see Viewing the image pull source.

Preparing your mirror host

Before you perform the mirror procedure, you must prepare the host to retrieve content and push it to the remote location.

Installing the OpenShift CLI by downloading the binary

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 4.13. 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
```

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
```

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
```

After you install the OpenShift CLI, it is available using the oc command:

$ oc <command>

Configuring credentials that allow images to be mirrored

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

Do not use this image registry credentials file as the pull secret when you install a cluster. If you provide this file when you install cluster, all of the machines in the cluster will have write access to your mirror registry.

This process requires that you have write access to a container image registry on the mirror registry and adds the credentials to a registry pull secret.

Prerequisites

You configured a mirror registry to use in your disconnected environment.
You identified an image repository location on your mirror registry to mirror images into.
You provisioned a mirror registry account that allows images to be uploaded to that image repository.

Procedure

Complete the following steps on the installation host:

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

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	For `<mirror_registry>`, 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	For `<credentials>`, 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}"

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
```

The Cluster Samples Operator in a disconnected environment

In a disconnected environment, you must take additional steps after you install a cluster to configure the Cluster Samples Operator. Review the following information in preparation.

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.

Mirroring Operator catalogs for use with disconnected clusters

You can mirror the Operator contents of a Red Hat-provided catalog, or a custom catalog, into a container image registry using the oc adm catalog mirror command. The target registry must support Docker v2-2. For a cluster on a restricted network, this registry can be one that the cluster has network access to, such as a mirror registry created during a restricted network cluster installation.

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.
Running oc adm catalog 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.

The oc adm catalog mirror command also automatically mirrors the index image that is specified during the mirroring process, whether it be a Red Hat-provided index image or your own custom-built index image, to the target registry. You can then use the mirrored index image to create a catalog source that allows Operator Lifecycle Manager (OLM) to load the mirrored catalog onto your OKD cluster.

Additional resources

Using Operator Lifecycle Manager on restricted networks

Prerequisites

Mirroring Operator catalogs for use with disconnected clusters has the following prerequisites:

Workstation with unrestricted network access.
podman version 1.9.3 or later.
Access to a mirror registry that supports Docker v2-2.
On your mirror registry, decide which namespace to use for storing mirrored Operator content. For example, you might create an olm-mirror namespace.
If your mirror registry does not have internet access, connect removable media to your workstation with unrestricted network access.
If you are working with private registries, including registry.redhat.io, set the REG_CREDS environment variable to the file path of your registry credentials for use in later steps. For example, for the podman CLI:
```
$ REG_CREDS=${XDG_RUNTIME_DIR}/containers/auth.json
```

Extracting and mirroring catalog contents

The oc adm catalog mirror command extracts the contents of an index image to generate the manifests required for mirroring. The default behavior of the command generates manifests, then automatically mirrors all of the image content from the index image, as well as the index image itself, to your mirror registry.

Alternatively, if your mirror registry is on a completely disconnected, or airgapped, host, you can first mirror the content to removable media, move the media to the disconnected environment, then mirror the content from the media to the registry.

Mirroring catalog contents to registries on the same network

If your mirror registry is co-located on the same network as your workstation with unrestricted network access, take the following actions on your workstation.

Procedure

If your mirror registry requires authentication, run the following command to log in to the registry:
```
$ podman login <mirror_registry>
```

Run the following command to extract and mirror the content to the mirror registry:

$ oc adm catalog mirror \
    <index_image> \ (1)
    <mirror_registry>:<port>/<namespace> \ (2)
    [-a ${REG_CREDS}] \ (3)
    [--insecure] \ (4)
    [--index-filter-by-os='<platform>/<arch>'] \ (5)
    [--manifests-only] (6)

1	Specify the index image for the catalog that you want to mirror.
2	Specify the fully qualified domain name (FQDN) for the target registry and namespace to mirror the Operator contents to, where `<namespace>` is any existing namespace on the registry. For example, you might create an `olm-mirror` namespace to push all mirrored content to.
3	Optional: If required, specify the location of your registry credentials file. `{REG_CREDS}` is required for `registry.redhat.io`.
4	Optional: If you do not want to configure trust for the target registry, add the `—insecure` flag.
5	Optional: Specify which platform and architecture of the index image to select when multiple variants are available. Images are passed as `‘<platform>/<arch>[/<variant>]’`. This does not apply to images referenced by the index. Valid values are `linux/amd64`, `linux/ppc64le`, `linux/s390x`, `linux/arm64`.
6	Optional: Generate only the manifests required for mirroring without actually mirroring the image content to a registry. This option can be useful for reviewing what will be mirrored, and lets you make any changes to the mapping list, if you require only a subset of packages. You can then use the `mapping.txt` file with the `oc image mirror` command to mirror the modified list of images in a later step. This flag is intended for only advanced selective mirroring of content from the catalog.

Example output

src image has index label for database path: /database/index.db
using database path mapping: /database/index.db:/tmp/153048078
wrote database to /tmp/153048078 (1)
...
wrote mirroring manifests to manifests-catalog-1614211642 (2)

1	Directory for the temporary `index.db` database generated by the command.
2	Record the manifests directory name that is generated. This directory is referenced in subsequent procedures.

Red Hat Quay does not support nested repositories. As a result, running the oc adm catalog mirror command will fail with a 401 unauthorized error. As a workaround, you can use the —max-components=2 option when running the oc adm catalog mirror command to disable the creation of nested repositories. For more information on this workaround, see the Unauthorized error thrown while using catalog mirror command with Quay registry Knowledgebase Solution.

Additional resources

Architecture and operating system support for Operators

Mirroring catalog contents to airgapped registries

If your mirror registry is on a completely disconnected, or airgapped, host, take the following actions.

Procedure

Run the following command on your workstation with unrestricted network access to mirror the content to local files:

$ oc adm catalog mirror \
    <index_image> \ (1)
    file:///local/index \ (2)
    -a ${REG_CREDS} \ (3)
    --insecure \ (4)
    --index-filter-by-os='<platform>/<arch>' (5)

1	Specify the index image for the catalog that you want to mirror.
2	Specify the content to mirror to local files in your current directory.
3	Optional: If required, specify the location of your registry credentials file.
4	Optional: If you do not want to configure trust for the target registry, add the `—insecure` flag.
5	Optional: Specify which platform and architecture of the index image to select when multiple variants are available. Images are specified as `‘<platform>/<arch>[/<variant>]’`. This does not apply to images referenced by the index. Valid values are `linux/amd64`, `linux/ppc64le`, `linux/s390x`, `linux/arm64`, and `.*`

Example output

...
info: Mirroring completed in 5.93s (5.915MB/s)
wrote mirroring manifests to manifests-my-index-1614985528 (1)
To upload local images to a registry, run:
    oc adm catalog mirror file://local/index/myrepo/my-index:v1 REGISTRY/REPOSITORY (2)

1	Record the manifests directory name that is generated. This directory is referenced in subsequent procedures.
2	Record the expanded `file://` path that is based on your provided index image. This path is referenced in a subsequent step.

This command creates a v2/ directory in your current directory.

Copy the v2/ directory to removable media.
Physically remove the media and attach it to a host in the disconnected environment that has access to the mirror registry.
If your mirror registry requires authentication, run the following command on your host in the disconnected environment to log in to the registry:
```
$ podman login <mirror_registry>
```

Run the following command from the parent directory containing the v2/ directory to upload the images from local files to the mirror registry:

$ oc adm catalog mirror \
    file://local/index/<repo>/<index_image>:<tag> \ (1)
    <mirror_registry>:<port>/<namespace> \ (2)
    -a ${REG_CREDS} \ (3)
    --insecure \ (4)
    --index-filter-by-os='<platform>/<arch>' (5)

1	Specify the `file://` path from the previous command output.
2	Specify the fully qualified domain name (FQDN) for the target registry and namespace to mirror the Operator contents to, where `<namespace>` is any existing namespace on the registry. For example, you might create an `olm-mirror` namespace to push all mirrored content to.
3	Optional: If required, specify the location of your registry credentials file.
4	Optional: If you do not want to configure trust for the target registry, add the `—insecure` flag.
5	Optional: Specify which platform and architecture of the index image to select when multiple variants are available. Images are specified as `‘<platform>/<arch>[/<variant>]’`. This does not apply to images referenced by the index. Valid values are `linux/amd64`, `linux/ppc64le`, `linux/s390x`, `linux/arm64`, and `.*`

Run the oc adm catalog mirror command again. Use the newly mirrored index image as the source and the same mirror registry namespace used in the previous step as the target:

$ oc adm catalog mirror \
    <mirror_registry>:<port>/<index_image> \
    <mirror_registry>:<port>/<namespace> \
    --manifests-only \(1)
    [-a ${REG_CREDS}] \
    [--insecure]

1	The `—manifests-only` flag is required for this step so that the command does not copy all of the mirrored content again.

This step is required because the image mappings in the imageContentSourcePolicy.yaml file generated during the previous step must be updated from local paths to valid mirror locations. Failure to do so will cause errors when you create the ImageContentSourcePolicy object in a later step.

After you mirror the catalog, you can continue with the remainder of your cluster installation. After your cluster installation has finished successfully, you must specify the manifests directory from this procedure to create the ImageContentSourcePolicy and CatalogSource objects. These objects are required to enable installation of Operators from OperatorHub.

Additional resources

Architecture and operating system support for Operators

Generated manifests

After mirroring Operator catalog content to your mirror registry, a manifests directory is generated in your current directory.

If you mirrored content to a registry on the same network, the directory name takes the following pattern:

manifests-<index_image_name>-<random_number>

If you mirrored content to a registry on a disconnected host in the previous section, the directory name takes the following pattern:

manifests-index/<namespace>/<index_image_name>-<random_number>

The manifests directory name is referenced in subsequent procedures.

The manifests directory contains the following files, some of which might require further modification:

The catalogSource.yaml file is a basic definition for a CatalogSource object that is pre-populated with your index image tag and other relevant metadata. This file can be used as is or modified to add the catalog source to your cluster.

If you mirrored the content to local files, you must modify your catalogSource.yaml file to remove any backslash (/) characters from the metadata.name field. Otherwise, when you attempt to create the object, it fails with an “invalid resource name” error.

The imageContentSourcePolicy.yaml file defines an ImageContentSourcePolicy object that can configure nodes to translate between the image references stored in Operator manifests and the mirrored registry.

If your cluster uses an ImageContentSourcePolicy object to configure repository mirroring, you can use only global pull secrets for mirrored registries. You cannot add a pull secret to a project.

The mapping.txt file contains all of the source images and where to map them in the target registry. This file is compatible with the oc image mirror command and can be used to further customize the mirroring configuration.

If you used the —manifests-only flag during the mirroring process and want to further trim the subset of packages to mirror, see the steps in the Mirroring a package manifest format catalog image procedure of the OKD 4.7 documentation about modifying your mapping.txt file and using the file with the oc image mirror command.

Post-installation requirements

Additional resources

Populating OperatorHub from mirrored Operator catalogs

Next steps

Install a cluster on infrastructure that you provision in your restricted network, such as on VMware vSphere, bare metal, or Amazon Web Services.

Additional resources

See Gathering data about specific features for more information about using must-gather.