Failed to start the instance i-25e3b943. Insufficient capacity.

Hi,

If you get this error when you try to launch an instance or restart a stopped instance, AWS does not currently have enough available On-Demand capacity to fulfill your request.

To resolve the issue, try the following:

1. Wait a few minutes and then submit your request again; capacity can shift frequently.
2. Submit a new request with a reduced number of instances. For example, if you're making a single request to launch 15 instances, try making 3 requests for 5 instances, or 15 requests for 1 instance instead.
3. If you're launching an instance, submit a new request without specifying an Availability Zone.
4. If you're launching an instance, submit a new request using a different instance type (which you can resize at a later stage). For more information, see Change the instance type.
5. If you are launching instances into a cluster placement group, you can get an insufficient capacity error. For more information, see Placement group rules and limitations.

Solution: If you receive this error, do the following:

• For troubleshooting steps, see Insufficient instance capacity.
• If the preceding troubleshooting steps don't resolve the problem, then you can move the instance to another VPC or to another subnet and Availability Zone.

To avoid insufficient capacity errors on critical machines, consider using On-Demand Capacity Reservations. To use an On-Demand Capacity Reservation, do the following:

• Create the Capacity Reservation in an Availability Zone.
• Launch critical instances into your Capacity Reservation. You can view real-time Capacity Reservation usage, and launch instances into it as needed.

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