Chapter 10. Using Red Hat subscriptions in builds
Use the following sections to run entitled builds on OpenShift Container Platform.
10.1. Creating an ImageStreamTag to the Red Hat Universal Base Image
To use Red Hat subscriptions within a build, you should create an ImageStream to reference the universal base image (UBI).
Builds that reference the UBI directly from registry.redhat.io will require a pull secret.
Prerequisites
- You must create a pull secret for registry.redhat.io, and link it to a user project.
Procedure
To create an
imagestreamtagin a single project:$ oc tag --source=docker registry.redhat.io/ubi7/ubi:latest ubi:latest
To create an
imagestreamtagin the OpenShift Container Platform namespace, making it available to developers in all projects:$ oc tag --source=docker registry.redhat.io/ubi7/ubi:latest ubi:latest -n openshift
10.2. Adding subscription entitlements as a build secret
Builds that use Red Hat subscriptions to install content must include the entitlement keys as a build secret.
Prerequisites
You must have access to Red Hat entitlements through your subscription, and the entitlements must have separate public and private key files.
Procedure
Create a secret containing your entitlements, ensuring that there are separate files containing the public and private keys:
$ oc create secret generic etc-pki-entitlement --from-file /path/to/entitlement/{ID}.pem \ > --from-file /path/to/entitlement/{ID}-key.pem ...Add the secret as a build input in the build configuration:
source: secrets: - secret: name: etc-pki-entitlement destinationDir: etc-pki-entitlement
There are two paths to pulling in the base RHEL image:
- Add the pull secret to registry.redhat.io to your project.
- Create an imagestream in the OpenShift namespace for the RHEL-based image. This makes the imagestream available across the cluster.
10.3. Running builds with Subscription Manager
10.3.1. Adding Subscription Manager configurations to builds
Builds that use the Subscription Manager to install content must provide appropriate configuration files and certificate authorities for subscribed repositories.
Prerequisites
You must have access to the Subscription Manager’s configuration and certificate authority files.
Procedure
Create a ConfigMap for the Subscription Manager configuration:
$ oc create configmap rhsm-conf --from-file /path/to/rhsm/rhsm.conf
Create a ConfigMap for the certificate authority:
$ oc create configmap rhsm-ca --from-file /path/to/rhsm/ca/redhat-uep.pem
Add the Subscription Manager configuration and certificate authority to the BuildConfig:
source: configMaps: - configMap: name: rhsm-conf destinationDir: rhsm-conf - configMap: name: rhsm-ca destinationDir: rhsm-ca
10.3.2. Docker builds using Subscription Manager
Docker strategy builds can use the Subscription Manager to install subscription content.
Prerequisites
The entitlement keys, subscription manager configuration, and subscription manager certificate authority must be added as build inputs.
Procedure
Use the following as an example Dockerfile to install content with the Subscription Manager:
FROM registry.redhat.io/rhel7:latest
USER root
# Copy entitlements
COPY ./etc-pki-entitlement /etc/pki/entitlement
# Copy subscription manager configurations
COPY ./rhsm-conf /etc/rhsm
COPY ./rhsm-ca /etc/rhsm/ca
# Delete /etc/rhsm-host to use entitlements from the build container
RUN rm /etc/rhsm-host && \
# Initialize /etc/yum.repos.d/redhat.repo
# See https://access.redhat.com/solutions/1443553
yum repolist --disablerepo=* && \
subscription-manager repos --enable <enabled-repo> && \
yum -y update && \
yum -y install <rpms> && \
# Remove entitlements and Subscription Manager configs
rm -rf /etc/pki/entitlement && \
rm -rf /etc/rhsm
# OpenShift requires images to run as non-root by default
USER 1001
ENTRYPOINT ["/bin/bash"]10.4. Running builds with Satellite subscriptions
10.4.1. Adding Satellite configurations to builds
Builds which use Satellite to install content must provide appropriate configurations to obtain content from Satellite repositories.
Prerequisites
You must provide or create a yum-compatible repository configuration file, that downloads content from your Satellite instance.
Procedure
Create a ConfigMap containing the Satellite repository configuration file:
$ oc create configmap yum-repos-d --from-file /path/to/satellite.repo
Add the Satellite repository configuration to the BuildConfig:
source: configMaps: - configMap: name: yum-repos-d destinationDir: yum.repos.d
10.4.2. Docker builds using Satellite subscriptions
Docker strategy builds can use Satellite repositories to install subscription content.
Prerequisites
The entitlement keys and Satellite repository configurations must be added as build inputs.
Procedure
Use the following as an example Dockerfile to install content with Satellite:
FROM registry.redhat.io/rhel7:latest
USER root
# Copy entitlements
COPY ./etc-pki-entitlement /etc/pki/entitlement
# Copy repository configuration
COPY ./yum.repos.d /etc/yum.repos.d
# Delete /etc/rhsm-host to use entitlements from the build container
RUN rm /etc/rhsm-host && \
# yum repository info provided by Satellite
yum -y update && \
yum -y install <rpms> && \
# Remove entitlements
rm -rf /etc/pki/entitlement
# OpenShift requires images to run as non-root by default
USER 1001
ENTRYPOINT ["/bin/bash"]10.5. Squash layers with docker builds
Docker builds normally create a layer representing each instruction in a Dockerfile. Setting the imageOptimizationPolicy to SkipLayers will merge all instructions into a single layer on top of the base image.
Procedure
-
Set the
imageOptimizationPolicytoSkipLayers:
strategy:
dockerStrategy:
imageOptimizationPolicy: SkipLayers 1- 1
- Layers are always squashed in OpenShift Container Platform 4.1.
10.6. Additional resources
- See Managing imagestreams for more information.
