从4.1开始cs提供了事件机制，这个技术有人了解没 3.1.6. Events Framework CLOUDSTACK-820:The event notification framework provides a means for the Management Server components to publish and subscribe to CloudStack events. Event notification is achieved by implementing the concept of event bus abstraction in the Management Server. An event bus is introduced in the Management Server that allows the CloudStackcomponents and extension plug-ins to subscribe to the events by using the Advanced Message Queuing Protocol (AMQP) client. In CloudStack, a default implementation of event bus is provided as a plug-in that uses the RabbitMQ AMQP client. The AMQP client pushes the published events to a compatible AMQP server. Therefore all the CloudStack events are published to an exchange in the AMQP server. A new event for state change, resource state change, is introduced as part of Event notification framework. Every resource, such as user VM, volume, NIC, network, public IP, snapshot, and template, is associated with a state machine and generates events as part of the state change. That implies that a change in the state of a resource results in a state change event, and the event is published in the corresponding state machine on the event bus. All the CloudStack events (alerts, action events, usage events) and the additional category of resource state change events, are published on to the events bus. See the Events Framework section of the Admin Guide for more information on using the events framework.
2013-09-12 陈珂
