Subscriber Sessions for Services with External Policy Management
In SRC Releases 4.0.0 and greater, you can use the SAE to manage services in an environment where policies are managed through an external policy management system for routers that run JunosE software. In these cases, the SAE creates subscriber sessions on interfaces that do not have default policies configured for the interface. The subscriber sessions on these interfaces act in the same way as subscriber sessions on interfaces that do have default policies configured.
When policies are managed by external software, you configure the SAE to manage an interface and configure an empty policy group to be assigned to the interface.
During a subscriber session, SRC can activate policies on an interface where policies are managed through an external policy management system. In this case, the following sequence of events occurs:
When the SAE activates the first service that installs a policy on a JunosE interface, the SAE attaches a policy list to that interface.
The policies in this policy list take precedence over policies previously attached to the interface through any mechanism other than COPS, such as through the CLI or RADIUS.
When the SAE activates more policies, all policies activated through the SAE are merged in the same interface attachment. For policies active on the interface, but not managed through COPS, the SAE replaces, rather than merges, the policies.
When the policies are deactivated, on deactivation of the last policy, the policies return to the state of the policies on the interface before the service was activated.