Subscribing to alarms in the target system

The probe sends a REST API request to subscribe to a query and to initiate a WebSocket connection with Cisco APIC to listen for push notifications. A notification is generated by Cisco APIC when a new fault is created, updated or deleted because of a user or system initiated action that changes the result of an active subscribed query.

The query response (with the subscription request) contains a subscription identifier (subscriptionId) that you use to refresh the subscription and to identify future notifications from this subscription. To continue to receive event notifications, you must periodically refresh each subscription during your API session. To refresh a subscription, send an HTTP GET message to the subscriptionRefresh API method with the parameter ID set to the subscriptionId. The default timeout period for a subscription in Cisco APIC is one minute.

Alarm subscription requests are configured by the following properties in the file:

  • subscribeRequestURI
  • subscribeRequestMethod
  • subscribeRequestContent
  • subscribeRefreshURI
  • subscribeRefreshMethod
  • subscribeRefreshContent
  • subscribeRefreshInterval

For details about these properties, see Configuring the transport module.