Auto Scaling:Overview

Notification rules

Auto Scaling supports the following notification rules:

• Advanced notification rule: This type of notification rule enables the automatic management of scaling events.
• Regular notification rule: If you use this type of notification rule, you must manually manage scaling events.

The following table describes the two types of notification rules.

Event notification examples

The following section provides examples of event notifications. For information about how to create an advanced notification rule, see Create an advanced notification rule.

• Event notifications by using CloudMonitor

  In this example, the Notification Method parameter is set to CloudMonitor, and the Event parameter is set to Successful Scale-out and Scale-out Started. After the scale-out activity is triggered, CloudMonitor receives a notification and displays the events. In the following figure, the events that a scale-out activity starts and the scale-out activity succeeds are displayed.

  
  Note In the CloudMonitor console, you can obtain dynamic information about your scaling group. You can also create alert rules. This way, CloudMonitor sends alert notifications to contacts by text message or email at the same time when alerts are reported. This improves O&M efficiency.
• Event notifications by using MNS topics

  In this example, the Notification Method parameter is set to MNS Topic, the MNS topic that is created in the region in which the scaling group resides is selected, and the Event parameter is set to Successful Scale-in and Scale-in Started. After the scale-in activity is triggered, Auto Scaling sends an event notification to the MNS topic. Then, the MNS topic pushes the notification to the subscribers of the topic. In the following figure, a scale-in activity is triggered. In the figure, the number of notifications that correspond to the MNS topic increases. You can click View Subscriptions to view the notification details.

  The MNS topic does not support the direct consumption of notifications. You must subscribe to the MNS topic by using an MNS queue, an HTTP request, or an email. When the MNS topic receives a notification, the MNS topic pushes the notification to the subscribers. This way, multiple subscribers separately consume the notification from the same publisher. This improves the efficiency of automatic management.

  
• Event notifications by using MNS queues

  In this example, the Notification Method parameter is set to MNS Queue, the MNS queue that is created in the region in which the scaling group resides is selected, and the Event parameter is set to Scale-out Failed and Scale-out Started. If the scale-out activity fails, Auto Scaling sends an event notification to the MNS queue and allows contacts to manage and consume the notification. In the following figure, a scale-out activity fails. In the figure, the number of available notifications that correspond to the MNS queue increases.

  You can manage notifications in a flexible manner. You can consume, delay, activate, or delete notifications based on your business requirements.

  

References

The following table describes the references of the event notification feature.