AWS SDK Version 3 for .NET
API Reference

AWS services or capabilities described in AWS Documentation may vary by region/location. Click Getting Started with Amazon AWS to see specific differences applicable to the China (Beijing) Region.

Creates a new, empty file system. The operation requires a creation token in the request that Amazon EFS uses to ensure idempotent creation (calling the operation with same creation token has no effect). If a file system does not currently exist that is owned by the caller's AWS account with the specified creation token, this operation does the following:

Otherwise, this operation returns a FileSystemAlreadyExists error with the ID of the existing file system.

For basic use cases, you can use a randomly generated UUID for the creation token.

The idempotent operation allows you to retry a CreateFileSystem call without risk of creating an extra file system. This can happen when an initial call fails in a way that leaves it uncertain whether or not a file system was actually created. An example might be that a transport level timeout occurred or your connection was reset. As long as you use the same creation token, if the initial call had succeeded in creating a file system, the client can learn of its existence from the FileSystemAlreadyExists error.

The CreateFileSystem call returns while the file system's lifecycle state is still creating. You can check the file system creation status by calling the DescribeFileSystems operation, which among other things returns the file system state.

This operation also takes an optional PerformanceMode parameter that you choose for your file system. We recommend generalPurpose performance mode for most file systems. File systems using the maxIO performance mode can scale to higher levels of aggregate throughput and operations per second with a tradeoff of slightly higher latencies for most file operations. The performance mode can't be changed after the file system has been created. For more information, see Amazon EFS: Performance Modes.

After the file system is fully created, Amazon EFS sets its lifecycle state to available, at which point you can create one or more mount targets for the file system in your VPC. For more information, see CreateMountTarget. You mount your Amazon EFS file system on an EC2 instances in your VPC via the mount target. For more information, see Amazon EFS: How it Works.

This operation requires permissions for the elasticfilesystem:CreateFileSystem action.


For .NET Core and PCL this operation is only available in asynchronous form. Please refer to CreateFileSystemAsync.

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


public virtual CreateFileSystemResponse CreateFileSystem(
         CreateFileSystemRequest request
Type: Amazon.ElasticFileSystem.Model.CreateFileSystemRequest

Container for the necessary parameters to execute the CreateFileSystem service method.

Return Value
The response from the CreateFileSystem service method, as returned by ElasticFileSystem.


BadRequestException Returned if the request is malformed or contains an error such as an invalid parameter value or a missing required parameter.
FileSystemAlreadyExistsException Returned if the file system you are trying to create already exists, with the creation token you provided.
FileSystemLimitExceededException Returned if the AWS account has already created the maximum number of file systems allowed per account.
InsufficientThroughputCapacityException Returned if there's not enough capacity to provision additional throughput. This value might be returned when you try to create a file system in provisioned throughput mode, when you attempt to increase the provisioned throughput of an existing file system, or when you attempt to change an existing file system from bursting to provisioned throughput mode.
InternalServerErrorException Returned if an error occurred on the server side.
ThroughputLimitExceededException Returned if the throughput mode or amount of provisioned throughput can't be changed because the throughput limit of 1024 MiB/s has been reached.


This operation creates a new file system with the default generalpurpose performance mode.

To create a new file system

var response = client.CreateFileSystem(new CreateFileSystemRequest 
    CreationToken = "tokenstring",
    PerformanceMode = "generalPurpose"

DateTime creationTime = response.CreationTime;
string creationToken = response.CreationToken;
string fileSystemId = response.FileSystemId;
string lifeCycleState = response.LifeCycleState;
integer numberOfMountTargets = response.NumberOfMountTargets;
string ownerId = response.OwnerId;
string performanceMode = response.PerformanceMode;
FileSystemSize sizeInBytes = response.SizeInBytes;


Version Information

.NET Framework:
Supported in: 4.5, 4.0, 3.5

Portable Class Library:
Supported in: Windows Store Apps
Supported in: Windows Phone 8.1
Supported in: Xamarin Android
Supported in: Xamarin iOS (Unified)
Supported in: Xamarin.Forms

See Also