AWS Instance Scheduler

1. Services Supported by Instance Scheduler

Service	Resource Type	Notes
Amazon EC2	Instances	Start/stop instances in a VPC or public subnet based on schedule
Amazon RDS	DB instances	Start/stop RDS database instances (Aurora, PostgreSQL, MySQL, SQL Server, etc.)
Amazon Redshift	Clusters	Start/stop Redshift clusters
Amazon Aurora	DB clusters	Aurora DB clusters can also be scheduled (stopping/starting in supported regions)

Basically, Instance Scheduler handles resources that support start and stop operations.

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2. How Instance Scheduler Accesses Services

• Deployed via AWS CloudFormation template.

• Creates an IAM role with permissions to:

  • Start/stop resources (ec2:StartInstances, rds:StartDBInstance, etc.)
  • Read tags and resource metadata
  • Write logs to CloudWatch Logs

• Scheduler uses tags on resources to decide which resources to manage.

  • Example: Schedule=BusinessHours

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3. Key Features

Feature	Description
Tag-based targeting	Only resources with a specific tag are scheduled
Multiple schedules	Can define different schedules (business hours, weekends, holidays)
Monitoring & logs	Uses CloudWatch logs to track start/stop operations
Flexible timing	Supports cron expressions, UTC offsets, and time zones

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4. Important Notes

• Works only with services that support start/stop; cannot schedule services that are always running (like DynamoDB, Lambda, S3).
• Aurora Serverless v2 doesn’t need Instance Scheduler — it auto-scales.

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✅ Summary Table

Question	Answer
Supported resources	EC2, RDS (instances & Aurora clusters), Redshift
Access method	IAM role created by CloudFormation
Selection method	Tag-based (Schedule tag by default)
Scheduling flexibility	Cron expressions, time zones, multiple schedules