Administrators can configure custom serving certificates for the public host names of the OpenShift Container Platform API and web console. This can be done during an advanced installation or configured after installation.

Configuring Custom Certificates with Ansible

During advanced installations, custom certificates can be configured using the openshift_master_named_certificates and openshift_master_overwrite_named_certificates parameters, which are configurable in the inventory file. More details are available about configuring custom certificates with Ansible.

Example 1. Example Custom Certificate Configuration with Ansible
# Configure custom named certificates
# NOTE: openshift_master_named_certificates is cached on masters and is an
# additive fact, meaning that each run with a different set of certificates
# will add the newly provided certificates to the cached set of certificates.
# An optional CA may be specified for each named certificate. CAs will
# be added to the OpenShift CA bundle which allows for the named
# certificate to be served for internal cluster communication.
# If you would like openshift_master_named_certificates to be overwritten with
# the provided value, specify openshift_master_overwrite_named_certificates.
# Provide local certificate paths which will be deployed to masters
openshift_master_named_certificates=[{"certfile": "/path/on/host/to/custom1.crt", "keyfile": "/path/on/host/to/custom1.key", "cafile": "/path/on/host/to/custom-ca1.crt"}]
# Detected names may be overridden by specifying the "names" key
#openshift_master_named_certificates=[{"certfile": "/path/on/host/to/custom1.crt", "keyfile": "/path/on/host/to/custom1.key", "names": ["public-master-host.com"], "cafile": "/path/on/host/to/custom-ca1.crt"}]

Configuring Custom Certificates

In the master configuration file you can list the namedCertificates section in the assetConfig.servingInfo section so the custom certificate serves up for the web console, and in the servingInfo section so the custom certificate serves up for the CLI and other API calls. Multiple certificates can be configured this way and each certificate may be associated with multiple host names or wildcards.

A default certificate must be configured in the servingInfo.certFile and servingInfo.keyFile configuration sections in addition to namedCertificates.

The namedCertificates section should only be configured for the host name associated with the masterPublicURL, assetConfig.publicURL, and oauthConfig.assetPublicURL settings. Using a custom serving certificate for the host name associated with the masterURL will result in TLS errors as infrastructure components will attempt to contact the master API using the internal masterURL host.

Example 2. Custom Certificates Configuration
  - certFile: custom.crt
    keyFile: custom.key
    - "customhost.com"
    - "api.customhost.com"
    - "console.customhost.com"
  - certFile: wildcard.crt
    keyFile: wildcard.key
    - "*.wildcardhost.com"

Relative paths are resolved relative to the master configuration file. Restart the server to pick up the configuration changes.