:doc:`EFS <../../efs>` / Client / create_mount_target

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create_mount_target
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.. py:method:: EFS.Client.create_mount_target(**kwargs)

  

  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 <https://docs.aws.amazon.com/efs/latest/ug/how-it-works.html>`__.

   

  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:

   

  
  * The file system ID for which you are creating the mount target.
   
  * A subnet ID, which determines the following: 

    
    * The VPC in which Amazon EFS creates the mount target
     
    * The Availability Zone in which Amazon EFS creates the mount target
     
    * The IP address range from which Amazon EFS selects the IP address of the mount target (if you don't specify an IP address in the request)
    

  
  

   

  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 <https://docs.aws.amazon.com/efs/latest/ug/how-it-works.html#how-it-works-implementation>`__.

   

  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:

   

  
  * Must belong to the same VPC as the subnets of the existing mount targets
   
  * Must not be in the same Availability Zone as any of the subnets of the existing mount targets
  

   

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

   

  
  * Creates a new mount target in the specified subnet.
   
  * Also creates a new network interface in the subnet as follows: 

    
    * If the request provides an ``IpAddress``, Amazon EFS assigns that IP address to the network interface. Otherwise, Amazon EFS assigns a free address in the subnet (in the same way that the Amazon EC2 ``CreateNetworkInterface`` call does when a request does not specify a primary private IP address).
     
    * If the request provides ``SecurityGroups``, this network interface is associated with those security groups. Otherwise, it belongs to the default security group for the subnet's VPC.
     
    * Assigns the description ``Mount target fsmt-id for file system fs-id`` where ``fsmt-id`` is the mount target ID, and ``fs-id`` is the ``FileSystemId``.
     
    * Sets the ``requesterManaged`` property of the network interface to ``true``, and the ``requesterId`` value to ``EFS``.
    

   

  Each Amazon EFS mount target has one corresponding requester-managed EC2 network interface. After the network interface is created, Amazon EFS sets the ``NetworkInterfaceId`` field in the mount target's description to the network interface ID, and the ``IpAddress`` field to its address. If network interface creation fails, the entire ``CreateMountTarget`` operation fails.

  
  

   

  .. note::

    

    The ``CreateMountTarget`` call returns only after creating the network interface, but while the mount target state is still ``creating``, you can check the mount target creation status by calling the  DescribeMountTargets operation, which among other things returns the mount target state.

    

   

  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 pricing <http://aws.amazon.com/efs/pricing/>`__. 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:

   

  
  * ``elasticfilesystem:CreateMountTarget``
  

   

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

   

  
  * ``ec2:DescribeSubnets``
   
  * ``ec2:DescribeNetworkInterfaces``
   
  * ``ec2:CreateNetworkInterface``
  

  

  See also: `AWS API Documentation <https://docs.aws.amazon.com/goto/WebAPI/elasticfilesystem-2015-02-01/CreateMountTarget>`_  


  **Request Syntax**
  ::

    response = client.create_mount_target(
        FileSystemId='string',
        SubnetId='string',
        IpAddress='string',
        Ipv6Address='string',
        IpAddressType='IPV4_ONLY'|'IPV6_ONLY'|'DUAL_STACK',
        SecurityGroups=[
            'string',
        ]
    )
    
  :type FileSystemId: string
  :param FileSystemId: **[REQUIRED]** 

    The ID of the file system for which to create the mount target.

    

  
  :type SubnetId: string
  :param SubnetId: **[REQUIRED]** 

    The ID of the subnet to add the mount target in. For One Zone file systems, use the subnet that is associated with the file system's Availability Zone.

    

  
  :type IpAddress: string
  :param IpAddress: 

    If the IP address type for the mount target is IPv4, then specify the IPv4 address within the address range of the specified subnet.

    

  
  :type Ipv6Address: string
  :param Ipv6Address: 

    If the IP address type for the mount target is IPv6, then specify the IPv6 address within the address range of the specified subnet.

    

  
  :type IpAddressType: string
  :param IpAddressType: 

    Specify the type of IP address of the mount target you are creating. Options are IPv4, dual stack, or IPv6. If you don’t specify an IpAddressType, then IPv4 is used.

     

    
    * IPV4_ONLY – Create mount target with IPv4 only subnet or dual-stack subnet.
     
    * DUAL_STACK – Create mount target with dual-stack subnet.
     
    * IPV6_ONLY – Create mount target with IPv6 only subnet.
    

     

    .. note::

      

      Creating IPv6 mount target only ENI in dual-stack subnet is not supported.

      

    

  
  :type SecurityGroups: list
  :param SecurityGroups: 

    VPC security group IDs, of the form ``sg-xxxxxxxx``. These must be for the same VPC as the subnet specified. The maximum number of security groups depends on account quota. For more information, see `Amazon VPC Quotas <https://docs.aws.amazon.com/vpc/latest/userguide/amazon-vpc-limits.html>`__ in the *Amazon VPC User Guide* (see the **Security Groups** table).

    

  
    - *(string) --* 

    

  
  :rtype: dict
  :returns: 
    
    **Response Syntax**

    
    ::

      {
          'OwnerId': 'string',
          'MountTargetId': 'string',
          'FileSystemId': 'string',
          'SubnetId': 'string',
          'LifeCycleState': 'creating'|'available'|'updating'|'deleting'|'deleted'|'error',
          'IpAddress': 'string',
          'Ipv6Address': 'string',
          'NetworkInterfaceId': 'string',
          'AvailabilityZoneId': 'string',
          'AvailabilityZoneName': 'string',
          'VpcId': 'string'
      }
      
    **Response Structure**

    

    - *(dict) --* 

      Provides a description of a mount target.

      
      

      - **OwnerId** *(string) --* 

        Amazon Web Services account ID that owns the resource.

        
      

      - **MountTargetId** *(string) --* 

        System-assigned mount target ID.

        
      

      - **FileSystemId** *(string) --* 

        The ID of the file system for which the mount target is intended.

        
      

      - **SubnetId** *(string) --* 

        The ID of the mount target's subnet.

        
      

      - **LifeCycleState** *(string) --* 

        Lifecycle state of the mount target.

        
      

      - **IpAddress** *(string) --* 

        Address at which the file system can be mounted by using the mount target.

        
      

      - **Ipv6Address** *(string) --* 

        The IPv6 address for the mount target.

        
      

      - **NetworkInterfaceId** *(string) --* 

        The ID of the network interface that Amazon EFS created when it created the mount target.

        
      

      - **AvailabilityZoneId** *(string) --* 

        The unique and consistent identifier of the Availability Zone that the mount target resides in. For example, ``use1-az1`` is an AZ ID for the us-east-1 Region and it has the same location in every Amazon Web Services account.

        
      

      - **AvailabilityZoneName** *(string) --* 

        The name of the Availability Zone in which the mount target is located. Availability Zones are independently mapped to names for each Amazon Web Services account. For example, the Availability Zone ``us-east-1a`` for your Amazon Web Services account might not be the same location as ``us-east-1a`` for another Amazon Web Services account.

        
      

      - **VpcId** *(string) --* 

        The virtual private cloud (VPC) ID that the mount target is configured in.

        
  
  **Exceptions**
  
  *   :py:class:`EFS.Client.exceptions.BadRequest`

  
  *   :py:class:`EFS.Client.exceptions.InternalServerError`

  
  *   :py:class:`EFS.Client.exceptions.FileSystemNotFound`

  
  *   :py:class:`EFS.Client.exceptions.IncorrectFileSystemLifeCycleState`

  
  *   :py:class:`EFS.Client.exceptions.MountTargetConflict`

  
  *   :py:class:`EFS.Client.exceptions.SubnetNotFound`

  
  *   :py:class:`EFS.Client.exceptions.NoFreeAddressesInSubnet`

  
  *   :py:class:`EFS.Client.exceptions.IpAddressInUse`

  
  *   :py:class:`EFS.Client.exceptions.NetworkInterfaceLimitExceeded`

  
  *   :py:class:`EFS.Client.exceptions.SecurityGroupLimitExceeded`

  
  *   :py:class:`EFS.Client.exceptions.SecurityGroupNotFound`

  
  *   :py:class:`EFS.Client.exceptions.UnsupportedAvailabilityZone`

  
  *   :py:class:`EFS.Client.exceptions.AvailabilityZonesMismatch`

  

  **Examples**

  This operation creates a new mount target for an EFS file system.
  ::

    response = client.create_mount_target(
        FileSystemId='fs-01234567',
        SubnetId='subnet-1234abcd',
    )
    
    print(response)

  
  Expected Output:
  ::

    {
        'FileSystemId': 'fs-01234567',
        'IpAddress': '192.0.0.2',
        'LifeCycleState': 'creating',
        'MountTargetId': 'fsmt-12340abc',
        'NetworkInterfaceId': 'eni-cedf6789',
        'OwnerId': '012345678912',
        'SubnetId': 'subnet-1234abcd',
        'ResponseMetadata': {
            '...': '...',
        },
    }

  