3.7. Managing Custom Domain Aliases

Developers can designate custom domain aliases for applications to use DNS entries other than the domains generated by OpenShift Enterprise. By default, developers cannot create aliases that are in the cloud domain where the applications are created. For example, a developer could not create the alias app.example.com or my-app.example.com for an application that was created in the cloud domain example.com. This restriction prevents confusion or possible name collisions.
Enabling the ALLOW_ALIAS_IN_DOMAIN setting in the /etc/openshift/broker.conf file on the broker host allows developers to create aliases within the cloud domain, provided the alias does not take the form <name>-<name>.<cloud-domain>. Aliases taking this standard form of application names are rejected to prevent conflicts. For example, while a developer could now create the alias app.example.com for an application that was created in the cloud domain example.com, they still could not create the alias my-app.example.com because it takes the standard form.

Important

While the ALLOW_ALIAS_IN_DOMAIN setting is enabled, only standard name collisions are prevented. Collisions with high-availability application names are not prevented, which, should they occur on the same node host, could result in traffic being routed to the wrong gear on the node host. OpenShift Enterprise still does not create a DNS entry for the alias; that is an external step.

Procedure 3.3. To Allow Custom Domain Aliases in the Cloud Domain:

  1. Edit the /etc/openshift/broker.conf file on the broker host and set the ALLOW_ALIAS_IN_DOMAIN setting to "true": 
    ALLOW_ALIAS_IN_DOMAIN="true"
  2. Restart the broker service: 
    # service openshift-broker restart