AWS EC2/RDS Instance Schedule

This article instructs on using the EC2/RDS scheduler, which starts and stops EC2/RDS instances based on the cloudaware:scheduler tag value. The schedule tag value may consist of several fields separated by spaces, with each field in the format key=value.

1 IAM Policy
2 Tag Keys
3 Tag Examples

IAM Policy

To grant Cloudaware necessary permissions, apply the following policy in your AWS console:

{
 "Version": "2012-10-17",
 "Statement": [
  {
   "Sid": "CaInstanceScheduler",
   "Effect": "Allow",
   "Action": [
    "ec2:DescribeInstances",
    "ec2:StartInstances",
    "ec2:StopInstances",
    "rds:DescribeDBInstances",
    "rds:ListTagsForResource",
    "rds:StartDBInstance",
    "rds:StopDBInstance"
   ],
   "Resource": [
    "*"
   ]
  }
 ]
}

You can also download the policy in your Cloudaware account. For that, go to Admin → AWS Accounts → ADD AMAZON ACCOUNT → Using Access & Secret Keys → select Instance Scheduler in 'CLOUDAWARE IAM POLICIES'.

Tag Keys

The list of tag keys that are used to set up instance start/stop:

Key	Description

Key	Description
tz (required)	Timezone to be used by the scheduler. Use Area/Location style from IANA Time Zone Database: `tz=America/New_York`
default (required)	Default instance work hours. Can be either numeric or range with a hyphen separated by slashes `/`. Use `off` to specify that the instance should be stopped all that day or `on` to specify that the instance should be running. The work hours should be specified in 24-hour format.
mon, tue, wed, thu, fri, sat, sun (optional)	Instance work hours for the current day. The format is the same as the key `default`. Example 1. Work hours: `default=9-16 sat=off sun=off` The instance will run from 9:00 to 16:59 all days, except Saturday and Sunday. Example 2. Work hours: `default=off wed=9/14-17` The instance will run only on Wednesday from 9:00 to 9:59 and from 14:00 to 17:59.
policy (optional)	Scheduler mode. Can be `start_at_time` or `stop_at_time`, meaning that the scheduler will check and change the instance status only at the time defined with keys `default` and `mon .. sun`.

Learn more about tagging resources in Cloudaware here.

Tag Examples

default=9-17 sat=9-11/15-17 sun=off tz=America/New_York

Description:

instance work hours	from Monday to Friday: `9:00-17:59`; Saturday: `9:00-11:59` and `15:00-17:59`; Sunday: completely off;
schedule timezone	New York (EST);

Use the 'default=off' to specify exceptions in work hours for an instance. The instance will be off all time, except for specific periods, for example:

default=off wed=0-5 tz=America/New_York

Description:

instance work hours	Wednesday: `00:00-5:59`;
schedule timezone	New York (EST);

To configure an instance to operate only from 8 AM to 6 PM on weekdays and remain off during nights and weekends, use the following schedule:

mon=8-18 tue=8-18 wed=8-18 thu=8-18 fri=8-18 sat=off sun=off default=off tz=America/New_York

Description:

instance work hours	from Monday to Friday: `8:00-18:59`; Saturday-Sunday: off
schedule timezone	New York (EST);

For instances that operate across midnight, configure a sophisticated scheduling pattern. For example, if an instance runs from Monday through Friday, operating from midnight to 2 AM and again from 10 PM to midnight, the configuration may be:

mon=0-2/22-24 tue=0-2/22-24 wed=0-2/22-24 thu=0-2/22-24 fri=0-2/22-24 sat=off sun=off default=off tz=America/New_York

Description:

instance work hours	from Monday to Friday: `0:00-2:00` and `22-0:00`; Saturday-Sunday: off
schedule timezone	New York (EST);

This approach allows for precise control over resource utilization and cost management.