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Chapter 14. Setting up additional trusted certificate authorities for builds

Use the following sections to set up additional certificate authorities (CA) to be trusted by builds when pulling images from an image registry.

The procedure requires a cluster administrator to create a ConfigMap and add additional CAs as keys in the configmap.

  • The ConfigMap must be created in the openshift-config namespace.

  • domain is the key in the ConfigMap; value is the PEM-encoded certificate.

    • Each CA must be associated with a domain. The domain format is hostname[..port].
  • The ConfigMap name must be set in the image.config.openshift.io/cluster cluster scoped configuration resource’s spec.additionalTrustedCA field.

You can add certificate authorities (CAs) to the cluster for use when pushing and pulling images via the following procedure.

Prerequisites

  • You must have cluster administrator privileges.
  • You must have access to the registry’s public certificates, usually a hostname/ca.crt file located in the /etc/docker/certs.d/ directory.

Procedure

  1. Create a ConfigMap in the openshift-config namespace containing the trusted certificates for the registries that use self-signed certificates. For each CA file, ensure the key in the ConfigMap is the registry’s hostname in the hostname[..port] format: 

    $ oc create configmap registry-cas -n openshift-config \
--from-file=myregistry.corp.com..5000=/etc/docker/certs.d/myregistry.corp.com:5000/ca.crt \
--from-file=otherregistry.com=/etc/docker/certs.d/otherregistry.com/ca.crt
    Copy to Clipboard Toggle word wrap

  2. Update the cluster image configuration: 

    $ oc patch image.config.openshift.io/cluster --patch '{"spec":{"additionalTrustedCA":{"name":"registry-cas"}}}' --type=merge
    Copy to Clipboard Toggle word wrap

14.2. Additional resources
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