CreateMountTarget

Creates a mount target for a file system. You can then mount the file system on EC2 instances by using the mount target.

You can create one mount target in each Availability Zone in your VPC. All EC2 instances in a VPC within a given Availability Zone share a single mount target for a given file system. If you have multiple subnets in an Availability Zone, you create a mount target in one of the subnets. EC2 instances do not need to be in the same subnet as the mount target in order to access their file system.

You can create only one mount target for a One Zone file system. You must create that mount target in the same Availability Zone in which the file system is located. Use the AvailabilityZoneName and AvailabiltyZoneId properties in the DescribeFileSystems response object to get this information. Use the subnetId associated with the file system's Availability Zone when creating the mount target.

For more information, see Amazon EFS: How it Works.

To create a mount target for a file system, the file system's lifecycle state must be available. For more information, see DescribeFileSystems.

In the request, provide the following:

After creating the mount target, Amazon EFS returns a response that includes, a MountTargetId and an IpAddress. You use this IP address when mounting the file system in an EC2 instance. You can also use the mount target's DNS name when mounting the file system. The EC2 instance on which you mount the file system by using the mount target can resolve the mount target's DNS name to its IP address. For more information, see How it Works: Implementation Overview.

Note that you can create mount targets for a file system in only one VPC, and there can be only one mount target per Availability Zone. That is, if the file system already has one or more mount targets created for it, the subnet specified in the request to add another mount target must meet the following requirements:

If the request satisfies the requirements, Amazon EFS does the following:

We recommend that you create a mount target in each of the Availability Zones. There are cost considerations for using a file system in an Availability Zone through a mount target created in another Availability Zone. For more information, see Amazon EFS. In addition, by always using a mount target local to the instance's Availability Zone, you eliminate a partial failure scenario. If the Availability Zone in which your mount target is created goes down, then you can't access your file system through that mount target.

This operation requires permissions for the following action on the file system:

This operation also requires permissions for the following Amazon EC2 actions:

Request Syntax

POST /2015-02-01/mount-targets HTTP/1.1
Content-type: application/json

{
   "FileSystemId": "string",
   "IpAddress": "string",
   "SecurityGroups": [ "string" ],
   "SubnetId": "string"
}

URI Request Parameters

The request does not use any URI parameters.

Request Body

The request accepts the following data in JSON format.

Response Syntax

HTTP/1.1 200
Content-type: application/json

{
   "AvailabilityZoneId": "string",
   "AvailabilityZoneName": "string",
   "FileSystemId": "string",
   "IpAddress": "string",
   "LifeCycleState": "string",
   "MountTargetId": "string",
   "NetworkInterfaceId": "string",
   "OwnerId": "string",
   "SubnetId": "string",
   "VpcId": "string"
}

Response Elements

If the action is successful, the service sends back an HTTP 200 response.

The following data is returned in JSON format by the service.

Errors

Examples

Add a mount target to a file system

The following request creates a mount target for a file system. The request specifies values for only the required FileSystemId and SubnetId parameters. The request does not provide the optional IpAddress and SecurityGroups parameters. For IpAddress, the operation uses one of the available IP addresses in the specified subnet. And, the operation uses the default security group associated with the VPC for the SecurityGroups.

Sample Request

POST /2015-02-01/mount-targets HTTP/1.1 
Host: elasticfilesystem.us-west-2.amazonaws.com
x-amz-date: 20140620T221118Z
Authorization: <...>
Content-Type: application/json
Content-Length: 160

{"SubnetId": "subnet-748c5d03", "FileSystemId": "fs-01234567"}

Sample Response

HTTP/1.1 200 OK
x-amzn-RequestId: 01234567-89ab-cdef-0123-456789abcdef
Content-Type: application/json
Content-Length: 252

{
    "MountTargetId": "fsmt-55a4413c",
    "NetworkInterfaceId": "eni-01234567",
    "FileSystemId": "fs-01234567",
    "LifeCycleState": "available",
    "SubnetId": "subnet-01234567",
    "OwnerId": "231243201240",
    "IpAddress": "172.31.22.183"
}

Add a mount target to a file system

The following request specifies all the request parameters to create a mount target.

Sample Request

POST /2015-02-01/mount-targets HTTP/1.1 
Host: elasticfilesystem.us-west-2.amazonaws.com
x-amz-date: 20140620T221118Z
Authorization: <...>
Content-Type: application/json
Content-Length: 160

{
   "FileSystemId":"fs-01234567",
   "SubnetId":"subnet-01234567",
   "IpAddress":"10.0.2.42",
   "SecurityGroups":[
      "sg-01234567"
   ]
}

Sample Response

HTTP/1.1 200 OK
x-amzn-RequestId: 01234567-89ab-cdef-0123-456789abcdef
Content-Type: application/json
Content-Length: 252

{
   "OwnerId":"251839141158",
   "MountTargetId":"fsmt-9a13661e",
   "FileSystemId":"fs-01234567",
   "SubnetId":"subnet-fd04ff94",
   "LifeCycleState":"available",
   "IpAddress":"10.0.2.42",
   "NetworkInterfaceId":"eni-1bcb7772"
}

See Also

For more information about using this API in one of the language-specific AWS SDKs, see the following: