The event notification feature helps you monitor the scaling activities. It can automatically send messages to CloudMonitor or Message Service (MNS), providing you with timely information on scaling groups to improve automatic management.

Event notification methods

Supported event notification methods include sending messages to CloudMonitor system events, MNS topics, and MNS queues.

In CloudMonitor, you can query and view statistics on system events of various cloud services, such as Auto Scaling. You can also obtain up-to-date information about scaling groups. For more information about the event monitoring feature of CloudMonitor, see View cloud service events.

Message Service offers two service models: MNS topic and MNS queue. Message Service is a distributed message service that helps you easily transfer data and notification messages among distributed components, and build loosely coupled systems. For more information about the features of MNS topics and MNS queues, see Message Service overview.
  • The MNS queue model supports point-to-point sending and receiving of messages. It is designed to deliver a highly reliable and concurrent consumption model in a point-to-point manner. Each message in a queue can only be consumed by a single consumer.
  • The MNS topic model supports one-to-many publishing and subscription of messages. It is designed to publish and subscribe to messages and send notifications in a one-to-many manner. The model also allows you to publish messages in various ways.

The following section provides examples of each event notification method. For more information about the parameter configuration, see Create an event notification.

Example of event notifications through CloudMonitor

You have created an event notification in which Notification Method is set to CloudMonitor and Event Types to Successful Scale-Outs and The scale-out activities for the specified scaling group are running. After a scale-out activity of a scaling group succeeds, CloudMonitor receives an event notification and displays the event. The following figure shows the notification results of the successful scale-out activity. Two events are displayed in the results, including The scale-out activities for the specified scaling group are running and Successful Scale-Outs.

In the CloudMonitor console, you can view the status of scaling groups and create alarm rules to notify multiple alarm contacts through SMS messages and emails. This helps improve operations and maintenance (O&M) efficiency.

Example of event notifications through an MNS topic

You have created an event notification in which Notification Method is set to MNS Topic and Event Types to Successful Scale-Ins and The scale-in activities for the specified scaling group are running. After a scale-in activity of a scaling group succeeds, the specified MNS topic receives an event notification and sends it to its subscribers. The following figure shows the notification results of the successful scale-in activity. The number displayed in the Message Count column corresponding to the MNS topic has increased. You can view the subscribers for message details.

The MNS topic does not allow direct consumption of messages. You must subscribe to the MNS topic through an MNS queue, HTTP request, or email. When the MNS topic receives a message, it pushes the message to subscribers. In this way, multiple subscribers separately consume messages from the same publisher, realizing efficient automatic management.

Example of event notifications through an MNS queue

You have created an event notification in which Notification Method is set to MNS Queue and Event Types to Failed Scale-Outs and The scale-out activities for the specified scaling group are running. After a scale-out activity of a scaling group fails, the specified MNS queue receives an event notification and allows you to configure the messages for consumption. The following figure shows the notification results of the failed scale-out activity. The number displayed in the Active Messages column corresponding to the MNS queue has increased.

You can consume, delay, activate, or delete the messages as needed, realizing automatic management through event notifications.