AWS SDK Version 3 for .NET
API Reference

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Describes the specified instances or all instances.

If you specify instance IDs, the output includes information for only the specified instances. If you specify filters, the output includes information for only those instances that meet the filter criteria. If you do not specify instance IDs or filters, the output includes information for all instances, which can affect performance. We recommend that you use pagination to ensure that the operation returns quickly and successfully.

If you specify an instance ID that is not valid, an error is returned. If you specify an instance that you do not own, it is not included in the output.

Recently terminated instances might appear in the returned results. This interval is usually less than one hour.

If you describe instances in the rare case where an Availability Zone is experiencing a service disruption and you specify instance IDs that are in the affected zone, or do not specify any instance IDs at all, the call fails. If you describe instances and specify only instance IDs that are in an unaffected zone, the call works normally.


This is an asynchronous operation using the standard naming convention for .NET 4.5 or higher. For .NET 3.5 the operation is implemented as a pair of methods using the standard naming convention of BeginDescribeInstances and EndDescribeInstances.

Namespace: Amazon.EC2
Assembly: AWSSDK.EC2.dll
Version: 3.x.y.z


public virtual Task<DescribeInstancesResponse> DescribeInstancesAsync(
         CancellationToken cancellationToken


Type: System.Threading.CancellationToken

A cancellation token that can be used by other objects or threads to receive notice of cancellation.

Return Value

The response from the DescribeInstances service method, as returned by EC2.

Version Information

.NET Core App:
Supported in: 3.1

.NET Standard:
Supported in: 2.0

.NET Framework:
Supported in: 4.5

See Also