Registry
Configuring registries for OpenShift Container Platform
Abstract
Chapter 1. OpenShift Container Platform registry overview
OpenShift Container Platform can build images from your source code, deploy them, and manage their lifecycle. It provides an internal, integrated container image registry that can be deployed in your OpenShift Container Platform environment to locally manage images. This overview contains reference information and links for registries commonly used with OpenShift Container Platform, with a focus on the internal image registry.
1.1. Glossary of common terms for OpenShift Container Platform registry
This glossary defines the common terms that are used in the registry content.
- container
- Lightweight and executable images that consist software and all its dependencies. Because containers virtualize the operating system, you can run containers in data center, a public or private cloud, or your local host.
- Image Registry Operator
-
The Image Registry Operator runs in the
openshift-image-registry
namespace, and manages the registry instance in that location. - image repository
- An image repository is a collection of related container images and tags identifying images.
- mirror registry
- The mirror registry is a registry that holds the mirror of OpenShift Container Platform images.
- namespace
- A namespace isolates groups of resources within a single cluster.
- OpenShift Container Platform registry
- OpenShift Container Platform registry is the registry provided by OpenShift Container Platform to manage images.
- pod
- The pod is the smallest logical unit in Kubernetes. A pod is comprised of one or more containers to run in a worker node.
- private registry
- A registry is a server that implements the container image registry API. A private registry is a registry that requires authentication to allow users access its contents.
- public registry
- A registry is a server that implements the container image registry API. A public registry is a registry that serves its contently publicly.
- Quay.io
- A public Red Hat Quay Container Registry instance provided and maintained by Red Hat, that serves most of the container images and Operators to OpenShift Container Platform clusters.
- registry authentication
- To push and pull images to and from private image repositories, the registry needs to authenticate its users with credentials.
- route
- Exposes a service to allow for network access to pods from users and applications outside the OpenShift Container Platform instance.
- scale down
- To decrease the number of replicas.
- scale up
- To increase the number of replicas.
- service
- A service exposes a running application on a set of pods.
1.2. Integrated OpenShift Container Platform registry
OpenShift Container Platform provides a built-in container image registry that runs as a standard workload on the cluster. The registry is configured and managed by an infrastructure Operator. It provides an out-of-the-box solution for users to manage the images that run their workloads, and runs on top of the existing cluster infrastructure. This registry can be scaled up or down like any other cluster workload and does not require specific infrastructure provisioning. In addition, it is integrated into the cluster user authentication and authorization system, which means that access to create and retrieve images is controlled by defining user permissions on the image resources.
The registry is typically used as a publication target for images built on the cluster, as well as being a source of images for workloads running on the cluster. When a new image is pushed to the registry, the cluster is notified of the new image and other components can react to and consume the updated image.
Image data is stored in two locations. The actual image data is stored in a configurable storage location, such as cloud storage or a filesystem volume. The image metadata, which is exposed by the standard cluster APIs and is used to perform access control, is stored as standard API resources, specifically images and imagestreams.
Additional resources
1.3. Third-party registries
OpenShift Container Platform can create containers using images from third-party registries, but it is unlikely that these registries offer the same image notification support as the integrated OpenShift Container Platform registry. In this situation, OpenShift Container Platform will fetch tags from the remote registry upon imagestream creation. To refresh the fetched tags, run oc import-image <stream>
. When new images are detected, the previously described build and deployment reactions occur.
1.3.1. Authentication
OpenShift Container Platform can communicate with registries to access private image repositories using credentials supplied by the user. This allows OpenShift Container Platform to push and pull images to and from private repositories.
1.3.1.1. Registry authentication with Podman
Some container image registries require access authorization. Podman is an open source tool for managing containers and container images and interacting with image registries. You can use Podman to authenticate your credentials, pull the registry image, and store local images in a local file system. The following is a generic example of authenticating the registry with Podman.
Procedure
- Use the Red Hat Ecosystem Catalog to search for specific container images from the Red Hat Repository and select the required image.
- Click Get this image to find the command for your container image.
Login by running the following command and entering your username and password to authenticate:
$ podman login registry.redhat.io Username:<your_registry_account_username> Password:<your_registry_account_password>
Download the image and save it locally by running the following command:
$ podman pull registry.redhat.io/<repository_name>
1.4. Red Hat Quay registries
If you need an enterprise-quality container image registry, Red Hat Quay is available both as a hosted service and as software you can install in your own data center or cloud environment. Advanced registry features in Red Hat Quay include geo-replication, image scanning, and the ability to roll back images.
Visit the Quay.io site to set up your own hosted Quay registry account. After that, follow the Quay Tutorial to log in to the Quay registry and start managing your images.
You can access your Red Hat Quay registry from OpenShift Container Platform like any remote container image registry.
Additional resources
1.5. Authentication enabled Red Hat registry
All container images available through the Container images section of the Red Hat Ecosystem Catalog are hosted on an image registry, registry.redhat.io
.
The registry, registry.redhat.io
, requires authentication for access to images and hosted content on OpenShift Container Platform. Following the move to the new registry, the existing registry will be available for a period of time.
OpenShift Container Platform pulls images from registry.redhat.io
, so you must configure your cluster to use it.
The new registry uses standard OAuth mechanisms for authentication, with the following methods:
- Authentication token. Tokens, which are generated by administrators, are service accounts that give systems the ability to authenticate against the container image registry. Service accounts are not affected by changes in user accounts, so the token authentication method is reliable and resilient. This is the only supported authentication option for production clusters.
-
Web username and password. This is the standard set of credentials you use to log in to resources such as
access.redhat.com
. While it is possible to use this authentication method with OpenShift Container Platform, it is not supported for production deployments. Restrict this authentication method to stand-alone projects outside OpenShift Container Platform.
You can use podman login
with your credentials, either username and password or authentication token, to access content on the new registry.
All imagestreams point to the new registry, which uses the installation pull secret to authenticate.
You must place your credentials in either of the following places:
-
openshift
namespace. Your credentials must exist in theopenshift
namespace so that the imagestreams in theopenshift
namespace can import. - Your host. Your credentials must exist on your host because Kubernetes uses the credentials from your host when it goes to pull images.
Additional resources
Chapter 2. Image Registry Operator in OpenShift Container Platform
2.1. Image Registry on cloud platforms and OpenStack
The Image Registry Operator installs a single instance of the OpenShift Container Platform registry, and manages all registry configuration, including setting up registry storage.
Storage is only automatically configured when you install an installer-provisioned infrastructure cluster on AWS, GCP, Azure, or OpenStack.
When you install or upgrade an installer-provisioned infrastructure cluster on AWS or Azure, the Image Registry Operator sets the spec.storage.managementState
parameter to Managed
. If the spec.storage.managementState
parameter is set to Unmanaged
, the Image Registry Operator takes no action related to storage.
After the control plane deploys, the Operator will create a default configs.imageregistry.operator.openshift.io
resource instance based on configuration detected in the cluster.
If insufficient information is available to define a complete configs.imageregistry.operator.openshift.io
resource, the incomplete resource will be defined and the Operator will update the resource status with information about what is missing.
The Image Registry Operator runs in the openshift-image-registry
namespace, and manages the registry instance in that location as well. All configuration and workload resources for the registry reside in that namespace.
The Image Registry Operator’s behavior for managing the pruner is orthogonal to the managementState
specified on the ClusterOperator
object for the Image Registry Operator. If the Image Registry Operator is not in the Managed
state, the image pruner can still be configured and managed by the Pruning
custom resource.
However, the managementState
of the Image Registry Operator alters the behavior of the deployed image pruner job:
-
Managed
: the--prune-registry
flag for the image pruner is set totrue
. -
Removed
: the--prune-registry
flag for the image pruner is set tofalse
, meaning it only prunes image metatdata in etcd. -
Unmanaged
: the--prune-registry
flag for the image pruner is set tofalse
.
2.2. Image Registry on bare metal and vSphere
2.2.1. Image registry removed during installation
On platforms that do not provide shareable object storage, the OpenShift Image Registry Operator bootstraps itself as Removed
. This allows openshift-installer
to complete installations on these platform types.
After installation, you must edit the Image Registry Operator configuration to switch the managementState
from Removed
to Managed
.
The Prometheus console provides an ImageRegistryRemoved
alert, for example:
"Image Registry has been removed. ImageStreamTags
, BuildConfigs
and DeploymentConfigs
which reference ImageStreamTags
may not work as expected. Please configure storage and update the config to Managed
state by editing configs.imageregistry.operator.openshift.io."
2.3. Image Registry Operator configuration parameters
The configs.imageregistry.operator.openshift.io
resource offers the following configuration parameters.
Parameter | Description |
---|---|
|
|
|
Sets
The supported values for
|
| Value needed by the registry to secure uploads, generated by default. |
| Defines the Proxy to be used when calling master API and upstream registries. |
|
|
| Indicates whether the registry instance should reject attempts to push new images or delete existing ones. |
| API Request Limit details. Controls how many parallel requests a given registry instance will handle before queuing additional requests. |
|
Determines whether or not an external route is defined using the default hostname. If enabled, the route uses re-encrypt encryption. Defaults to |
| Array of additional routes to create. You provide the hostname and certificate for the route. |
| Replica count for the registry. |
|
Controls whether to route all data through the registry, rather than redirecting to the back end. Defaults to |
|
The Image Registry Operator sets the
|
2.4. Enable the Image Registry default route with the Custom Resource Definition
In OpenShift Container Platform, the Registry
Operator controls the registry feature. The Operator is defined by the configs.imageregistry.operator.openshift.io
Custom Resource Definition (CRD).
If you need to automatically enable the Image Registry default route, patch the Image Registry Operator CRD.
Procedure
Patch the Image Registry Operator CRD:
$ oc patch configs.imageregistry.operator.openshift.io/cluster --type merge -p '{"spec":{"defaultRoute":true}}'
2.5. Configuring additional trust stores for image registry access
The image.config.openshift.io/cluster
custom resource can contain a reference to a config map that contains additional certificate authorities to be trusted during image registry access.
Prerequisites
- The certificate authorities (CA) must be PEM-encoded.
Procedure
You can create a config map in the openshift-config
namespace and use its name in AdditionalTrustedCA
in the image.config.openshift.io
custom resource to provide additional CAs that should be trusted when contacting external registries.
The config map key is the hostname of a registry with the port for which this CA is to be trusted, and the PEM certificate content is the value, for each additional registry CA to trust.
Image registry CA config map example
apiVersion: v1
kind: ConfigMap
metadata:
name: my-registry-ca
data:
registry.example.com: |
-----BEGIN CERTIFICATE-----
...
-----END CERTIFICATE-----
registry-with-port.example.com..5000: | 1
-----BEGIN CERTIFICATE-----
...
-----END CERTIFICATE-----
- 1
- If the registry has the port, such as
registry-with-port.example.com:5000
,:
should be replaced with..
.
You can configure additional CAs with the following procedure.
To configure an additional CA:
$ oc create configmap registry-config --from-file=<external_registry_address>=ca.crt -n openshift-config
$ oc edit image.config.openshift.io cluster
spec: additionalTrustedCA: name: registry-config
2.6. Configuring storage credentials for the Image Registry Operator
In addition to the configs.imageregistry.operator.openshift.io
and ConfigMap resources, storage credential configuration is provided to the Operator by a separate secret resource located within the openshift-image-registry
namespace.
The image-registry-private-configuration-user
secret provides credentials needed for storage access and management. It overrides the default credentials used by the Operator, if default credentials were found.
Procedure
Create an OpenShift Container Platform secret that contains the required keys.
$ oc create secret generic image-registry-private-configuration-user --from-literal=KEY1=value1 --from-literal=KEY2=value2 --namespace openshift-image-registry
2.7. Additional resources
Chapter 3. Setting up and configuring the registry
3.1. Configuring the registry for AWS user-provisioned infrastructure
3.1.1. Configuring a secret for the Image Registry Operator
In addition to the configs.imageregistry.operator.openshift.io
and ConfigMap resources, configuration is provided to the Operator by a separate secret resource located within the openshift-image-registry
namespace.
The image-registry-private-configuration-user
secret provides credentials needed for storage access and management. It overrides the default credentials used by the Operator, if default credentials were found.
For S3 on AWS storage, the secret is expected to contain two keys:
-
REGISTRY_STORAGE_S3_ACCESSKEY
-
REGISTRY_STORAGE_S3_SECRETKEY
Procedure
Create an OpenShift Container Platform secret that contains the required keys.
$ oc create secret generic image-registry-private-configuration-user --from-literal=REGISTRY_STORAGE_S3_ACCESSKEY=myaccesskey --from-literal=REGISTRY_STORAGE_S3_SECRETKEY=mysecretkey --namespace openshift-image-registry
3.1.2. Configuring registry storage for AWS with user-provisioned infrastructure
During installation, your cloud credentials are sufficient to create an Amazon S3 bucket and the Registry Operator will automatically configure storage.
If the Registry Operator cannot create an S3 bucket and automatically configure storage, you can create an S3 bucket and configure storage with the following procedure.
Prerequisites
- You have a cluster on AWS with user-provisioned infrastructure.
For Amazon S3 storage, the secret is expected to contain two keys:
-
REGISTRY_STORAGE_S3_ACCESSKEY
-
REGISTRY_STORAGE_S3_SECRETKEY
-
Procedure
Use the following procedure if the Registry Operator cannot create an S3 bucket and automatically configure storage.
- Set up a Bucket Lifecycle Policy to abort incomplete multipart uploads that are one day old.
Fill in the storage configuration in
configs.imageregistry.operator.openshift.io/cluster
:$ oc edit configs.imageregistry.operator.openshift.io/cluster
Example configuration
storage: s3: bucket: <bucket-name> region: <region-name>
To secure your registry images in AWS, block public access to the S3 bucket.
3.1.3. Image Registry Operator configuration parameters for AWS S3
The following configuration parameters are available for AWS S3 registry storage.
ImageRegistryConfigStorageS3
holds the information to configure the registry to use the AWS S3 service for back-end storage. See the S3 storage driver documentation for more information.
Parameter | Description |
---|---|
| Bucket is the bucket name in which you want to store the registry’s data. It is optional and is generated if not provided. |
| Region is the AWS region in which your bucket exists. It is optional and is set based on the installed AWS Region. |
| RegionEndpoint is the endpoint for S3 compatible storage services. It is optional and defaults based on the Region that is provided. |
| VirtualHostedStyle enables using S3 virtual hosted style bucket paths with a custom RegionEndpoint. It is optional and defaults to false. Set this parameter to deploy OpenShift Container Platform to hidden regions. |
| Encrypt specifies whether or not the registry stores the image in encrypted format. It is optional and defaults to false. |
| KeyID is the KMS key ID to use for encryption. It is optional. Encrypt must be true, or this parameter is ignored. |
| CloudFront configures Amazon Cloudfront as the storage middleware in a registry. It is optional. |
When the value of the regionEndpoint
parameter is configured to a URL of a Rados Gateway, an explicit port must not be specified. For example:
regionEndpoint: http://rook-ceph-rgw-ocs-storagecluster-cephobjectstore.openshift-storage.svc.cluster.local
3.2. Configuring the registry for GCP user-provisioned infrastructure
3.2.1. Configuring a secret for the Image Registry Operator
In addition to the configs.imageregistry.operator.openshift.io
and ConfigMap resources, configuration is provided to the Operator by a separate secret resource located within the openshift-image-registry
namespace.
The image-registry-private-configuration-user
secret provides credentials needed for storage access and management. It overrides the default credentials used by the Operator, if default credentials were found.
For GCS on GCP storage, the secret is expected to contain one key whose value is the contents of a credentials file provided by GCP:
-
REGISTRY_STORAGE_GCS_KEYFILE
Procedure
Create an OpenShift Container Platform secret that contains the required keys.
$ oc create secret generic image-registry-private-configuration-user --from-file=REGISTRY_STORAGE_GCS_KEYFILE=<path_to_keyfile> --namespace openshift-image-registry
3.2.2. Registry storage for GCP with user-provisioned infrastructure
You must set up the storage medium manually and configure the settings in the registry custom resource (CR).
Prerequisites
- A cluster on GCP with user-provisioned infrastructure.
- To configure registry storage for GCP, you need to provide Registry Operator cloud credentials.
For GCS on GCP storage, the secret is expected to contain one key whose value is the contents of a credentials file provided by GCP:
-
REGISTRY_STORAGE_GCS_KEYFILE
-
3.2.3. Image Registry Operator configuration parameters for GCP GCS
Procedure
The following configuration parameters are available for GCP GCS registry storage.
Parameter | Description |
---|---|
| Bucket is the bucket name in which you want to store the registry’s data. It is optional and is generated if not provided. |
| Region is the GCS location in which your bucket exists. It is optional and is set based on the installed GCS Region. |
| ProjectID is the Project ID of the GCP project that this bucket should be associated with. It is optional. |
| KeyID is the KMS key ID to use for encryption. It is optional because buckets are encrypted by default on GCP. This allows for the use of a custom encryption key. |
3.3. Configuring the registry for OpenStack user-provisioned infrastructure
You can configure the registry of a cluster that runs on your own Red Hat OpenStack Platform (RHOSP) infrastructure.
3.3.1. Configuring the Image Registry Operator to trust Swift storage
You must configure the Image Registry Operator to trust Red Hat OpenStack Platform (RHOSP) Swift storage.
Procedure
From a command line, enter the following command to change the value of the
spec.disableRedirect
field in theconfig.imageregistry
object totrue
:$ oc patch configs.imageregistry.operator.openshift.io cluster --type merge --patch '{"spec":{"disableRedirect":true}}'
3.3.2. Configuring a secret for the Image Registry Operator
In addition to the configs.imageregistry.operator.openshift.io
and ConfigMap resources, configuration is provided to the Operator by a separate secret resource located within the openshift-image-registry
namespace.
The image-registry-private-configuration-user
secret provides credentials needed for storage access and management. It overrides the default credentials used by the Operator, if default credentials were found.
For Swift on Red Hat OpenStack Platform (RHOSP) storage, the secret is expected to contain the following two keys:
-
REGISTRY_STORAGE_SWIFT_USER
-
REGISTRY_STORAGE_SWIFT_PASSWORD
Procedure
Create an OpenShift Container Platform secret that contains the required keys.
$ oc create secret generic image-registry-private-configuration-user --from-literal=REGISTRY_STORAGE_SWIFT_USER=<username> --from-literal=REGISTRY_STORAGE_SWIFT_PASSWORD=<password> -n openshift-image-registry
3.3.3. Registry storage for RHOSP with user-provisioned infrastructure
You must set up the storage medium manually and configure the settings in the registry custom resource (CR).
Prerequisites
- A cluster on Red Hat OpenStack Platform (RHOSP) with user-provisioned infrastructure.
- To configure registry storage for RHOSP, you need to provide Registry Operator cloud credentials.
For Swift on RHOSP storage, the secret is expected to contain the following two keys:
-
REGISTRY_STORAGE_SWIFT_USER
-
REGISTRY_STORAGE_SWIFT_PASSWORD
-
3.3.4. Image Registry Operator configuration parameters for RHOSP Swift
The following configuration parameters are available for Red Hat OpenStack Platform (RHOSP) Swift registry storage.
Parameter | Description |
---|---|
| Defines the URL for obtaining the authentication token. This value is optional. |
|
Specifies the Auth version of RHOSP, for example, |
| Defines the name of a Swift container for storing registry data. This value is optional. |
| Specifies the RHOSP domain name for the Identity v3 API. This value is optional. |
| Specifies the RHOSP domain ID for the Identity v3 API. This value is optional. |
| Defines the RHOSP tenant name to be used by the registry. This value is optional. |
| Defines the RHOSP tenant ID to be used by the registry. This value is optional. |
| Defines the RHOSP region in which the container exists. This value is optional. |
3.4. Configuring the registry for Azure user-provisioned infrastructure
3.4.1. Configuring a secret for the Image Registry Operator
In addition to the configs.imageregistry.operator.openshift.io
and ConfigMap resources, configuration is provided to the Operator by a separate secret resource located within the openshift-image-registry
namespace.
The image-registry-private-configuration-user
secret provides credentials needed for storage access and management. It overrides the default credentials used by the Operator, if default credentials were found.
For Azure registry storage, the secret is expected to contain one key whose value is the contents of a credentials file provided by Azure:
-
REGISTRY_STORAGE_AZURE_ACCOUNTKEY
Procedure
Create an OpenShift Container Platform secret that contains the required key.
$ oc create secret generic image-registry-private-configuration-user --from-literal=REGISTRY_STORAGE_AZURE_ACCOUNTKEY=<accountkey> --namespace openshift-image-registry
3.4.2. Configuring registry storage for Azure
During installation, your cloud credentials are sufficient to create Azure Blob Storage, and the Registry Operator automatically configures storage.
Prerequisites
- A cluster on Azure with user-provisioned infrastructure.
- To configure registry storage for Azure, provide Registry Operator cloud credentials.
For Azure storage the secret is expected to contain one key:
-
REGISTRY_STORAGE_AZURE_ACCOUNTKEY
-
Procedure
- Create an Azure storage container.
Fill in the storage configuration in
configs.imageregistry.operator.openshift.io/cluster
:$ oc edit configs.imageregistry.operator.openshift.io/cluster
Example configuration
storage: azure: accountName: <storage-account-name> container: <container-name>
3.4.3. Configuring registry storage for Azure Government
During installation, your cloud credentials are sufficient to create Azure Blob Storage, and the Registry Operator automatically configures storage.
Prerequisites
- A cluster on Azure with user-provisioned infrastructure in a government region.
- To configure registry storage for Azure, provide Registry Operator cloud credentials.
For Azure storage, the secret is expected to contain one key:
-
REGISTRY_STORAGE_AZURE_ACCOUNTKEY
-
Procedure
- Create an Azure storage container.
Fill in the storage configuration in
configs.imageregistry.operator.openshift.io/cluster
:$ oc edit configs.imageregistry.operator.openshift.io/cluster
Example configuration
storage: azure: accountName: <storage-account-name> container: <container-name> cloudName: AzureUSGovernmentCloud 1
- 1
cloudName
is the name of the Azure cloud environment, which can be used to configure the Azure SDK with the appropriate Azure API endpoints. Defaults toAzurePublicCloud
. You can also setcloudName
toAzureUSGovernmentCloud
,AzureChinaCloud
, orAzureGermanCloud
with sufficient credentials.
3.5. Configuring the registry for RHOSP
3.5.1. Configuring an image registry with custom storage on clusters that run on RHOSP
After you install a cluster on Red Hat OpenStack Platform (RHOSP), you can use a Cinder volume that is in a specific availability zone for registry storage.
Procedure
Create a YAML file that specifies the storage class and availability zone to use. For example:
apiVersion: storage.k8s.io/v1 kind: StorageClass metadata: name: custom-csi-storageclass provisioner: cinder.csi.openstack.org volumeBindingMode: WaitForFirstConsumer allowVolumeExpansion: true parameters: availability: <availability_zone_name>
NoteOpenShift Container Platform does not verify the existence of the availability zone you choose. Verify the name of the availability zone before you apply the configuration.
From a command line, apply the configuration:
$ oc apply -f <storage_class_file_name>
Example output
storageclass.storage.k8s.io/custom-csi-storageclass created
Create a YAML file that specifies a persistent volume claim (PVC) that uses your storage class and the
openshift-image-registry
namespace. For example:apiVersion: v1 kind: PersistentVolumeClaim metadata: name: csi-pvc-imageregistry namespace: openshift-image-registry 1 annotations: imageregistry.openshift.io: "true" spec: accessModes: - ReadWriteOnce volumeMode: Filesystem resources: requests: storage: 100Gi 2 storageClassName: <your_custom_storage_class> 3
From a command line, apply the configuration:
$ oc apply -f <pvc_file_name>
Example output
persistentvolumeclaim/csi-pvc-imageregistry created
Replace the original persistent volume claim in the image registry configuration with the new claim:
$ oc patch configs.imageregistry.operator.openshift.io/cluster --type 'json' -p='[{"op": "replace", "path": "/spec/storage/pvc/claim", "value": "csi-pvc-imageregistry"}]'
Example output
config.imageregistry.operator.openshift.io/cluster patched
Over the next several minutes, the configuration is updated.
Verification
To confirm that the registry is using the resources that you defined:
Verify that the PVC claim value is identical to the name that you provided in your PVC definition:
$ oc get configs.imageregistry.operator.openshift.io/cluster -o yaml
Example output
... status: ... managementState: Managed pvc: claim: csi-pvc-imageregistry ...
Verify that the status of the PVC is
Bound
:$ oc get pvc -n openshift-image-registry csi-pvc-imageregistry
Example output
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE csi-pvc-imageregistry Bound pvc-72a8f9c9-f462-11e8-b6b6-fa163e18b7b5 100Gi RWO custom-csi-storageclass 11m
3.6. Configuring the registry for bare metal
3.6.1. Image registry removed during installation
On platforms that do not provide shareable object storage, the OpenShift Image Registry Operator bootstraps itself as Removed
. This allows openshift-installer
to complete installations on these platform types.
After installation, you must edit the Image Registry Operator configuration to switch the managementState
from Removed
to Managed
.
The Prometheus console provides an ImageRegistryRemoved
alert, for example:
"Image Registry has been removed. ImageStreamTags
, BuildConfigs
and DeploymentConfigs
which reference ImageStreamTags
may not work as expected. Please configure storage and update the config to Managed
state by editing configs.imageregistry.operator.openshift.io."
3.6.2. Changing the image registry’s management state
To start the image registry, you must change the Image Registry Operator configuration’s managementState
from Removed
to Managed
.
Procedure
Change
managementState
Image Registry Operator configuration fromRemoved
toManaged
. For example:$ oc patch configs.imageregistry.operator.openshift.io cluster --type merge --patch '{"spec":{"managementState":"Managed"}}'
3.6.3. Image registry storage configuration
The Image Registry Operator is not initially available for platforms that do not provide default storage. After installation, you must configure your registry to use storage so that the Registry Operator is made available.
Instructions are shown for configuring a persistent volume, which is required for production clusters. Where applicable, instructions are shown for configuring an empty directory as the storage location, which is available for only non-production clusters.
Additional instructions are provided for allowing the image registry to use block storage types by using the Recreate
rollout strategy during upgrades.
3.6.4. Configuring registry storage for bare metal and other manual installations
As a cluster administrator, following installation you must configure your registry to use storage.
Prerequisites
-
You have access to the cluster as a user with the
cluster-admin
role. - You have a cluster that uses manually-provisioned Red Hat Enterprise Linux CoreOS (RHCOS) nodes, such as bare metal.
You have provisioned persistent storage for your cluster, such as Red Hat OpenShift Container Storage.
ImportantOpenShift Container Platform supports
ReadWriteOnce
access for image registry storage when you have only one replica.ReadWriteOnce
access also requires that the registry uses theRecreate
rollout strategy. To deploy an image registry that supports high availability with two or more replicas,ReadWriteMany
access is required.- Must have 100Gi capacity.
Procedure
To configure your registry to use storage, change the
spec.storage.pvc
in theconfigs.imageregistry/cluster
resource.NoteWhen using shared storage, review your security settings to prevent outside access.
Verify that you do not have a registry pod:
$ oc get pod -n openshift-image-registry -l docker-registry=default
Example output
No resourses found in openshift-image-registry namespace
NoteIf you do have a registry pod in your output, you do not need to continue with this procedure.
Check the registry configuration:
$ oc edit configs.imageregistry.operator.openshift.io
Example output
storage: pvc: claim:
Leave the
claim
field blank to allow the automatic creation of animage-registry-storage
PVC.Check the
clusteroperator
status:$ oc get clusteroperator image-registry
Example output
NAME VERSION AVAILABLE PROGRESSING DEGRADED SINCE MESSAGE image-registry 4.9 True False False 6h50m
Ensure that your registry is set to managed to enable building and pushing of images.
Run:
$ oc edit configs.imageregistry/cluster
Then, change the line
managementState: Removed
to
managementState: Managed
3.6.5. Configuring storage for the image registry in non-production clusters
You must configure storage for the Image Registry Operator. For non-production clusters, you can set the image registry to an empty directory. If you do so, all images are lost if you restart the registry.
Procedure
To set the image registry storage to an empty directory:
$ oc patch configs.imageregistry.operator.openshift.io cluster --type merge --patch '{"spec":{"storage":{"emptyDir":{}}}}'
WarningConfigure this option for only non-production clusters.
If you run this command before the Image Registry Operator initializes its components, the
oc patch
command fails with the following error:Error from server (NotFound): configs.imageregistry.operator.openshift.io "cluster" not found
Wait a few minutes and run the command again.
3.6.6. Configuring block registry storage
To allow the image registry to use block storage types during upgrades as a cluster administrator, you can use the Recreate
rollout strategy.
Block storage volumes are supported but not recommended for use with the image registry on production clusters. An installation where the registry is configured on block storage is not highly available because the registry cannot have more than one replica.
Procedure
To set the image registry storage as a block storage type, patch the registry so that it uses the
Recreate
rollout strategy and runs with only one (1
) replica:$ oc patch config.imageregistry.operator.openshift.io/cluster --type=merge -p '{"spec":{"rolloutStrategy":"Recreate","replicas":1}}'
- Provision the PV for the block storage device, and create a PVC for that volume. The requested block volume uses the ReadWriteOnce (RWO) access mode.
- Edit the registry configuration so that it references the correct PVC.
3.6.7. Additional resources
- For more details about configuring registry storage for bare metal, see Recommended configurable storage technology.
3.7. Configuring the registry for vSphere
3.7.1. Image registry removed during installation
On platforms that do not provide shareable object storage, the OpenShift Image Registry Operator bootstraps itself as Removed
. This allows openshift-installer
to complete installations on these platform types.
After installation, you must edit the Image Registry Operator configuration to switch the managementState
from Removed
to Managed
.
The Prometheus console provides an ImageRegistryRemoved
alert, for example:
"Image Registry has been removed. ImageStreamTags
, BuildConfigs
and DeploymentConfigs
which reference ImageStreamTags
may not work as expected. Please configure storage and update the config to Managed
state by editing configs.imageregistry.operator.openshift.io."
3.7.2. Changing the image registry’s management state
To start the image registry, you must change the Image Registry Operator configuration’s managementState
from Removed
to Managed
.
Procedure
Change
managementState
Image Registry Operator configuration fromRemoved
toManaged
. For example:$ oc patch configs.imageregistry.operator.openshift.io cluster --type merge --patch '{"spec":{"managementState":"Managed"}}'
3.7.2.1. Image registry storage configuration
The Image Registry Operator is not initially available for platforms that do not provide default storage. After installation, you must configure your registry to use storage so that the Registry Operator is made available.
Instructions are shown for configuring a persistent volume, which is required for production clusters. Where applicable, instructions are shown for configuring an empty directory as the storage location, which is available for only non-production clusters.
Additional instructions are provided for allowing the image registry to use block storage types by using the Recreate
rollout strategy during upgrades.
3.7.3. Configuring registry storage for VMware vSphere
As a cluster administrator, following installation you must configure your registry to use storage.
Prerequisites
- Cluster administrator permissions.
- A cluster on VMware vSphere.
Persistent storage provisioned for your cluster, such as Red Hat OpenShift Container Storage.
ImportantOpenShift Container Platform supports
ReadWriteOnce
access for image registry storage when you have only one replica.ReadWriteOnce
access also requires that the registry uses theRecreate
rollout strategy. To deploy an image registry that supports high availability with two or more replicas,ReadWriteMany
access is required.- Must have "100Gi" capacity.
Testing shows issues with using the NFS server on RHEL as storage backend for core services. This includes the OpenShift Container Registry and Quay, Prometheus for monitoring storage, and Elasticsearch for logging storage. Therefore, using RHEL NFS to back PVs used by core services is not recommended.
Other NFS implementations on the marketplace might not have these issues. Contact the individual NFS implementation vendor for more information on any testing that was possibly completed against these OpenShift Container Platform core components.
Procedure
To configure your registry to use storage, change the
spec.storage.pvc
in theconfigs.imageregistry/cluster
resource.NoteWhen using shared storage, review your security settings to prevent outside access.
Verify that you do not have a registry pod:
$ oc get pod -n openshift-image-registry -l docker-registry=default
Example output
No resourses found in openshift-image-registry namespace
NoteIf you do have a registry pod in your output, you do not need to continue with this procedure.
Check the registry configuration:
$ oc edit configs.imageregistry.operator.openshift.io
Example output
storage: pvc: claim: 1
- 1
- Leave the
claim
field blank to allow the automatic creation of animage-registry-storage
persistent volume claim (PVC). The PVC is generated based on the default storage class. However, be aware that the default storage class might provide ReadWriteOnce (RWO) volumes, such as a RADOS Block Device (RBD), which can cause issues when replicating to more than one replica.
Check the
clusteroperator
status:$ oc get clusteroperator image-registry
Example output
NAME VERSION AVAILABLE PROGRESSING DEGRADED SINCE MESSAGE image-registry 4.7 True False False 6h50m
3.7.4. Configuring storage for the image registry in non-production clusters
You must configure storage for the Image Registry Operator. For non-production clusters, you can set the image registry to an empty directory. If you do so, all images are lost if you restart the registry.
Procedure
To set the image registry storage to an empty directory:
$ oc patch configs.imageregistry.operator.openshift.io cluster --type merge --patch '{"spec":{"storage":{"emptyDir":{}}}}'
WarningConfigure this option for only non-production clusters.
If you run this command before the Image Registry Operator initializes its components, the
oc patch
command fails with the following error:Error from server (NotFound): configs.imageregistry.operator.openshift.io "cluster" not found
Wait a few minutes and run the command again.
3.7.5. Configuring block registry storage for VMware vSphere
To allow the image registry to use block storage types such as vSphere Virtual Machine Disk (VMDK) during upgrades as a cluster administrator, you can use the Recreate
rollout strategy.
Block storage volumes are supported but not recommended for use with image registry on production clusters. An installation where the registry is configured on block storage is not highly available because the registry cannot have more than one replica.
Procedure
To set the image registry storage as a block storage type, patch the registry so that it uses the
Recreate
rollout strategy and runs with only1
replica:$ oc patch config.imageregistry.operator.openshift.io/cluster --type=merge -p '{"spec":{"rolloutStrategy":"Recreate","replicas":1}}'
Provision the PV for the block storage device, and create a PVC for that volume. The requested block volume uses the ReadWriteOnce (RWO) access mode.
Create a
pvc.yaml
file with the following contents to define a VMware vSpherePersistentVolumeClaim
object:kind: PersistentVolumeClaim apiVersion: v1 metadata: name: image-registry-storage 1 namespace: openshift-image-registry 2 spec: accessModes: - ReadWriteOnce 3 resources: requests: storage: 100Gi 4
- 1
- A unique name that represents the
PersistentVolumeClaim
object. - 2
- The namespace for the
PersistentVolumeClaim
object, which isopenshift-image-registry
. - 3
- The access mode of the persistent volume claim. With
ReadWriteOnce
, the volume can be mounted with read and write permissions by a single node. - 4
- The size of the persistent volume claim.
Create the
PersistentVolumeClaim
object from the file:$ oc create -f pvc.yaml -n openshift-image-registry
Edit the registry configuration so that it references the correct PVC:
$ oc edit config.imageregistry.operator.openshift.io -o yaml
Example output
storage: pvc: claim: 1
- 1
- Creating a custom PVC allows you to leave the
claim
field blank for the default automatic creation of animage-registry-storage
PVC.
For instructions about configuring registry storage so that it references the correct PVC, see Configuring the registry for vSphere.
3.7.6. Additional resources
- For more details about configuring registry storage for vSphere, see Recommended configurable storage technology.
Chapter 4. Accessing the registry
Use the following sections for instructions on accessing the registry, including viewing logs and metrics, as well as securing and exposing the registry.
You can access the registry directly to invoke podman
commands. This allows you to push images to or pull them from the integrated registry directly using operations like podman push
or podman pull
. To do so, you must be logged in to the registry using the podman login
command. The operations you can perform depend on your user permissions, as described in the following sections.
4.1. Prerequisites
- You must have configured an identity provider (IDP).
For pulling images, for example when using the
podman pull
command, the user must have theregistry-viewer
role. To add this role, run the following command:$ oc policy add-role-to-user registry-viewer <user_name>
For writing or pushing images, for example when using the
podman push
command:The user must have the
registry-editor
role. To add this role, run the following command:$ oc policy add-role-to-user registry-editor <user_name>
- Your cluster must have an existing project where the images can be pushed to.
4.2. Accessing registry directly from the cluster
You can access the registry from inside the cluster.
Procedure
Access the registry from the cluster by using internal routes:
Access the node by getting the node’s name:
$ oc get nodes
$ oc debug nodes/<node_name>
To enable access to tools such as
oc
andpodman
on the node, change your root directory to/host
:sh-4.2# chroot /host
Log in to the container image registry by using your access token:
sh-4.2# oc login -u kubeadmin -p <password_from_install_log> https://api-int.<cluster_name>.<base_domain>:6443
sh-4.2# podman login -u kubeadmin -p $(oc whoami -t) image-registry.openshift-image-registry.svc:5000
You should see a message confirming login, such as:
Login Succeeded!
NoteYou can pass any value for the user name; the token contains all necessary information. Passing a user name that contains colons will result in a login failure.
Since the Image Registry Operator creates the route, it will likely be similar to
default-route-openshift-image-registry.<cluster_name>
.Perform
podman pull
andpodman push
operations against your registry:ImportantYou can pull arbitrary images, but if you have the system:registry role added, you can only push images to the registry in your project.
In the following examples, use:
Component Value <registry_ip>
172.30.124.220
<port>
5000
<project>
openshift
<image>
image
<tag>
omitted (defaults to
latest
)Pull an arbitrary image:
sh-4.2# podman pull <name.io>/<image>
Tag the new image with the form
<registry_ip>:<port>/<project>/<image>
. The project name must appear in this pull specification for OpenShift Container Platform to correctly place and later access the image in the registry:sh-4.2# podman tag <name.io>/<image> image-registry.openshift-image-registry.svc:5000/openshift/<image>
NoteYou must have the
system:image-builder
role for the specified project, which allows the user to write or push an image. Otherwise, thepodman push
in the next step will fail. To test, you can create a new project to push the image.Push the newly tagged image to your registry:
sh-4.2# podman push image-registry.openshift-image-registry.svc:5000/openshift/<image>
4.3. Checking the status of the registry pods
As a cluster administrator, you can list the image registry pods running in the openshift-image-registry
project and check their status.
Prerequisites
-
You have access to the cluster as a user with the
cluster-admin
role.
Procedure
List the pods in the
openshift-image-registry
project and view their status:$ oc get pods -n openshift-image-registry
Example output
NAME READY STATUS RESTARTS AGE cluster-image-registry-operator-764bd7f846-qqtpb 1/1 Running 0 78m image-registry-79fb4469f6-llrln 1/1 Running 0 77m node-ca-hjksc 1/1 Running 0 73m node-ca-tftj6 1/1 Running 0 77m node-ca-wb6ht 1/1 Running 0 77m node-ca-zvt9q 1/1 Running 0 74m
4.4. Viewing registry logs
You can view the logs for the registry by using the oc logs
command.
Procedure
Use the
oc logs
command with deployments to view the logs for the container image registry:$ oc logs deployments/image-registry -n openshift-image-registry
Example output
2015-05-01T19:48:36.300593110Z time="2015-05-01T19:48:36Z" level=info msg="version=v2.0.0+unknown" 2015-05-01T19:48:36.303294724Z time="2015-05-01T19:48:36Z" level=info msg="redis not configured" instance.id=9ed6c43d-23ee-453f-9a4b-031fea646002 2015-05-01T19:48:36.303422845Z time="2015-05-01T19:48:36Z" level=info msg="using inmemory layerinfo cache" instance.id=9ed6c43d-23ee-453f-9a4b-031fea646002 2015-05-01T19:48:36.303433991Z time="2015-05-01T19:48:36Z" level=info msg="Using OpenShift Auth handler" 2015-05-01T19:48:36.303439084Z time="2015-05-01T19:48:36Z" level=info msg="listening on :5000" instance.id=9ed6c43d-23ee-453f-9a4b-031fea646002
4.5. Accessing registry metrics
The OpenShift Container Registry provides an endpoint for Prometheus metrics. Prometheus is a stand-alone, open source systems monitoring and alerting toolkit.
The metrics are exposed at the /extensions/v2/metrics path of the registry endpoint.
Procedure
You can access the metrics by running a metrics query using a cluster role.
Cluster role
Create a cluster role if you do not already have one to access the metrics:
$ cat <<EOF | oc create -f - apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRole metadata: name: prometheus-scraper rules: - apiGroups: - image.openshift.io resources: - registry/metrics verbs: - get EOF
Add this role to a user, run the following command:
$ oc adm policy add-cluster-role-to-user prometheus-scraper <username>
Metrics query
Get the user token.
openshift: $ oc whoami -t
Run a metrics query in node or inside a pod, for example:
$ curl --insecure -s -u <user>:<secret> \ 1 https://image-registry.openshift-image-registry.svc:5000/extensions/v2/metrics | grep imageregistry | head -n 20
Example output
# HELP imageregistry_build_info A metric with a constant '1' value labeled by major, minor, git commit & git version from which the image registry was built. # TYPE imageregistry_build_info gauge imageregistry_build_info{gitCommit="9f72191",gitVersion="v3.11.0+9f72191-135-dirty",major="3",minor="11+"} 1 # HELP imageregistry_digest_cache_requests_total Total number of requests without scope to the digest cache. # TYPE imageregistry_digest_cache_requests_total counter imageregistry_digest_cache_requests_total{type="Hit"} 5 imageregistry_digest_cache_requests_total{type="Miss"} 24 # HELP imageregistry_digest_cache_scoped_requests_total Total number of scoped requests to the digest cache. # TYPE imageregistry_digest_cache_scoped_requests_total counter imageregistry_digest_cache_scoped_requests_total{type="Hit"} 33 imageregistry_digest_cache_scoped_requests_total{type="Miss"} 44 # HELP imageregistry_http_in_flight_requests A gauge of requests currently being served by the registry. # TYPE imageregistry_http_in_flight_requests gauge imageregistry_http_in_flight_requests 1 # HELP imageregistry_http_request_duration_seconds A histogram of latencies for requests to the registry. # TYPE imageregistry_http_request_duration_seconds summary imageregistry_http_request_duration_seconds{method="get",quantile="0.5"} 0.01296087 imageregistry_http_request_duration_seconds{method="get",quantile="0.9"} 0.014847248 imageregistry_http_request_duration_seconds{method="get",quantile="0.99"} 0.015981195 imageregistry_http_request_duration_seconds_sum{method="get"} 12.260727916000022
- 1
- The
<user>
object can be arbitrary, but<secret>
tag must use the user token.
4.6. Additional resources
- For more information on allowing pods in a project to reference images in another project, see Allowing pods to reference images across projects.
-
A
kubeadmin
can access the registry until deleted. See Removing the kubeadmin user for more information. - For more information on configuring an identity provider, see Understanding identity provider configuration.
Chapter 5. Exposing the registry
By default, the OpenShift Container Platform registry is secured during cluster installation so that it serves traffic through TLS. Unlike previous versions of OpenShift Container Platform, the registry is not exposed outside of the cluster at the time of installation.
5.1. Exposing a default registry manually
Instead of logging in to the default OpenShift Container Platform registry from within the cluster, you can gain external access to it by exposing it with a route. This external access enables you to log in to the registry from outside the cluster using the route address and to tag and push images to an existing project by using the route host.
Prerequisites:
The following prerequisites are automatically performed:
- Deploy the Registry Operator.
- Deploy the Ingress Operator.
Procedure
You can expose the route by using the defaultRoute
parameter in the configs.imageregistry.operator.openshift.io
resource.
To expose the registry using the defaultRoute
:
Set
defaultRoute
totrue
:$ oc patch configs.imageregistry.operator.openshift.io/cluster --patch '{"spec":{"defaultRoute":true}}' --type=merge
Get the default registry route:
$ HOST=$(oc get route default-route -n openshift-image-registry --template='{{ .spec.host }}')
Get the certificate of the Ingress Operator:
$ oc get secret -n openshift-ingress router-certs-default -o go-template='{{index .data "tls.crt"}}' | base64 -d | sudo tee /etc/pki/ca-trust/source/anchors/${HOST}.crt > /dev/null
Enable the cluster’s default certificate to trust the route using the following commands:
$ sudo update-ca-trust enable
Log in with podman using the default route:
$ sudo podman login -u kubeadmin -p $(oc whoami -t) $HOST
5.2. Exposing a secure registry manually
Instead of logging in to the OpenShift Container Platform registry from within the cluster, you can gain external access to it by exposing it with a route. This allows you to log in to the registry from outside the cluster using the route address, and to tag and push images to an existing project by using the route host.
Prerequisites:
The following prerequisites are automatically performed:
- Deploy the Registry Operator.
- Deploy the Ingress Operator.
Procedure
You can expose the route by using DefaultRoute
parameter in the configs.imageregistry.operator.openshift.io
resource or by using custom routes.
To expose the registry using DefaultRoute
:
Set
DefaultRoute
toTrue
:$ oc patch configs.imageregistry.operator.openshift.io/cluster --patch '{"spec":{"defaultRoute":true}}' --type=merge
Log in with
podman
:$ HOST=$(oc get route default-route -n openshift-image-registry --template='{{ .spec.host }}')
$ podman login -u kubeadmin -p $(oc whoami -t) --tls-verify=false $HOST 1
- 1
--tls-verify=false
is needed if the cluster’s default certificate for routes is untrusted. You can set a custom, trusted certificate as the default certificate with the Ingress Operator.
To expose the registry using custom routes:
Create a secret with your route’s TLS keys:
$ oc create secret tls public-route-tls \ -n openshift-image-registry \ --cert=</path/to/tls.crt> \ --key=</path/to/tls.key>
This step is optional. If you do not create a secret, the route uses the default TLS configuration from the Ingress Operator.
On the Registry Operator:
spec: routes: - name: public-routes hostname: myregistry.mycorp.organization secretName: public-route-tls ...
NoteOnly set
secretName
if you are providing a custom TLS configuration for the registry’s route.
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