AWS EC2/RDS Instance Schedule

The EC2/RDS scheduler starts and stops EC2/RDS instances based on the cloudaware:scheduler tag value. Schedule tag value may consist of several fields separated by a space, each field in the format key=value.

IAM Policy

To provide Cloudaware with necessary permissions for instance start/stop schedule, apply the following Instance Scheduler 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": [
    "*"
   ]
  }
 ]
}

The policy can be also downloaded in Cloudaware account: go to Admin → AWS Accounts → ADD AMAZON ACCOUNT → Using Access & Secret Keys → select Instance Scheduler in 'Please use one of those'.

Tag Keys

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

Key	Description
tz (required)	Timezone to be used by 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 the slashes `/`. It also can be the word `off` which mean that instance should be stopped all that day or `on` which mean that 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 current day. Format is the same as key `default`. Example 1. Work hours: default=9-16 sat=off sun=off Instance will be running from 9:00 to 16:59 all days except Saturday and Sunday. Example 2. Work hours: default=off wed=9/14-17 Instance will be running 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` which mean that the scheduler will check and change instance status only at 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 work hours for an instance. The instance will be off all time, except for specific time 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);

This configuration below can be used for instances to operate from 8 AM to 6 PM on weekdays, remain off during non-working hours, and also off on weekends:

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);

You can implement a sophisticated scheduling pattern when configuring instances with operational requirements that cross midnight. For example, to have an instance operate from Monday through Friday, running from midnight to 2 AM and again from 10 PM to midnight, use the following schedule configuration:

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.