Events in CloudWatch

• AWS has a new service for events which is called as Event Bridge

• Cloudwatch events are designed to be able to respond to changes in different AWS resources and services

• Using some rules that determine specific change or action or activity that tookplace, Cloudwatch events can be configured to respond accordingly.

• Amazon EventBridge

  • This is newer version of Amazon CloudWatch Events.
  • Event Bridge is a serverless event bus service that is designed to responds to events by triggering other events
  • Event bridge is very similar to Cloud Watch Events => it recieves events and responds to events from other services
  • Event bridge is different from Cloud Watch Events as it can respind to the events from sources others than AWS Services.
  • Events from Software as a Services or custom applications can be tied to EventBridge and we can respond Accordingly.

• Components of Cloudwatch Event:

  • Input Trigger:
    • This is what starts the process or the CloudWatch Event
    • It contains information that is useful for the behavior of the resulting trigger and how the event pattern behaves
    • The input trigger or event source can range from different AWS Services
    • In the Case of Event Bridge, in addition to AWS sources we can also get events from third party
      • PagerDuty
      • Opsgenie
      • Datadog
      • SugarCRM
  • Rule/event pattern:
    • The event pattern gives Cloudwatch Events all the information it needs to react to it
  • Target:
    • This is the destination service that reacts to the input trigger

• Activity: Lets try to use the events to notify the state changes (running -> shutdown etc…)

  • create a rule
  • Add a target
  • To configure specific instances

• Activity: Lets assume your organization wants to start some ec2 instances at 10:00 AM on every working day and shutdown ec2 instances at 7:00 PM to save costs

  • This is where the Schedule will be your input trigger
  • Lets try to create cron sytnax Refer Here
  • To know more about cloudwatch schedule expression Refer Here
  • The timezone over here is UTC => Convert to your timezone