AWS EventBridge Scheduler: Automate EC2 Scheduling with Ease

Takahiro Iwasa
2 min read
EventBridge Scheduler
This note describes how to automate starting and stopping of EC2 instances using EventBridge Scheduler.
Building
Start an EC2 instance for the test.
aws ec2 run-instances \ --image-id ami-0f9fe1d9214628296 \ --count 1 \ --instance-type t2.micro \ --security-group-ids <SECURITY_GROUP_IDS> \ --subnet-id <SUBNET_ID>
The ScheduleStartExpression
and ScheduleStopExpression
parameters on lines 11-16 define the schedule using cron expression.
AWSTemplateFormatVersion: '2010-09-09'Description: EC2 scheduler
Parameters: Prefix: Type: String Default: ec2-scheduler InstanceIds: Type: String Description: '"i-1234567890abcdefg", "..."' ScheduleStartExpression: Type: String Default: 'cron(0 7 * * ? *)' ScheduleStopExpression: Type: String Default: 'cron(0 22 * * ? *)' ScheduleTimezone: Type: String Description: IANA timezone identifier. For the full list, refer to https://en.wikipedia.org/wiki/List_of_tz_database_time_zones Default: UTC AllowedValues: - UTC - Japan
Resources: ScheduleStart: Type: AWS::Scheduler::Schedule Properties: Name: !Sub ${Prefix}-schedule-start ScheduleExpression: !Ref ScheduleStartExpression ScheduleExpressionTimezone: !Ref ScheduleTimezone FlexibleTimeWindow: Mode: 'OFF' State: ENABLED Target: Arn: arn:aws:scheduler:::aws-sdk:ec2:startInstances Input: !Sub |- { "InstanceIds": [${InstanceIds}] } RoleArn: !GetAtt Role.Arn
ScheduleStop: Type: AWS::Scheduler::Schedule Properties: Name: !Sub ${Prefix}-schedule-stop ScheduleExpression: !Ref ScheduleStopExpression ScheduleExpressionTimezone: !Ref ScheduleTimezone FlexibleTimeWindow: Mode: 'OFF' State: ENABLED Target: Arn: arn:aws:scheduler:::aws-sdk:ec2:stopInstances Input: !Sub |- { "InstanceIds": [${InstanceIds}] } RoleArn: !GetAtt Role.Arn
Role: Type: AWS::IAM::Role Properties: RoleName: !Sub ${Prefix}-role AssumeRolePolicyDocument: Version: 2012-10-17 Statement: - Effect: Allow Principal: Service: - scheduler.amazonaws.com Action: - sts:AssumeRole Policies: - PolicyName: ec2 PolicyDocument: Version: 2012-10-17 Statement: - Effect: Allow Action: - ec2:StartInstances - ec2:StopInstances Resource: !Sub arn:aws:ec2:${AWS::Region}:${AWS::AccountId}:instance/i-*
Deploy the CloudFormation stack with the following command:
aws cloudformation deploy \ --template-file ./template.yaml \ --stack-name ec2-scheduler \ --parameter-overrides InstanceIds='"<INSTANCE_ID1>", "<INSTANCE_ID2>"' \ --capabilities CAPABILITY_NAMED_IAM
Testing
The provisioned EventBridge Scheduler will automatically start the EC2 instance at 7:00 AM and stop it at 10:00 PM.
Cleaning Up
Clean up all the AWS resources provisioned during this example with the following command:
aws ec2 terminate-instances --instance-ids <INSTANCE_IDS>aws cloudformation delete-stack --stack-name ec2-scheduler