Modify an active Capacity Reservation

You can change the attributes of an active Capacity Reservation after you have created it. You cannot modify a Capacity Reservation after it has expired or after you have explicitly canceled it.

When modifying a Capacity Reservation, you can only increase or decrease the quantity and change the way in which it is released. You cannot change the instance type, EBS optimization, platform, Availability Zone, or instance eligibility of a Capacity Reservation. If you need to modify any of these attributes, we recommend that you cancel the reservation, and then create a new one with the required attributes.

If you specify a new quantity that exceeds your remaining On-Demand Instance limit for the selected instance type, the update fails.

To modify a Capacity Reservation using the console

1. Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.

2. Choose Capacity Reservations, select the Capacity Reservation to modify, and then choose Edit.

3. Modify the Quantity or Reservation ends options as needed, and choose Save changes.

To modify a Capacity Reservation using the AWS CLI

Use the modify-capacity-reservation command:

For example, the following command modifies a Capacity Reservation to reserve capacity for eight instances.

aws ec2 modify-capacity-reservation --capacity-reservation-id cr-1234567890abcdef0 --instance-count 8