Automatically mount file shares on an Amazon EC2 Linux instance - Amazon FSx for Windows File Server
To automatically mount a file share on an Amazon Linux EC2 instance not joined to your Active Directory
Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

Automatically mount file shares on an Amazon EC2 Linux instance

You can automatically mount your FSx for Windows File Server file share to access your FSx for Windows File Server file system whenever the Amazon EC2 Linux instance to which it's mounted reboots. To do so, add an entry to the /etc/fstab file on the EC2 instance. The /etc/fstab file contains information about file systems. The command mount -a, which runs during instance startup, mounts the file systems listed in the /etc/fstab file.

For an Amazon EC2 Linux instance that is not joined to your Active Directory, you can only mount an FSx for Windows File Server file share by using its private IP address. You can get the file system's private IP address using the Amazon FSx console, on the Network & security tab, in Preferred File Server IP Address.

The following procedure uses Microsoft NTLM authentication. You mount the file system as a user that is a member of the Microsoft Active Directory domain to which the FSx for Windows File Server file system is joined. You can retrieve the credentials for the user account from the creds.txt file using the following command.

$ cat creds.txt
username=user1
password=Password123
domain=EXAMPLE.COM

To automatically mount a file share on an Amazon Linux EC2 instance not joined to your Active Directory

To launch and configure the Amazon Linux EC2 instance

  1. Launch an Amazon Linux EC2 instance using the Amazon EC2 console. For more information, see Launch an instance in the Amazon EC2 User Guide.

  2. Connect to your instance. For more information, see Connect to your Linux instance in the Amazon EC2 User Guide.

  3. Run the following command to install the cifs-utils package. This package is used to mount network file systems like Amazon FSx on Linux.

    $ sudo yum install cifs-utils

  4. Create the /mnt/fsx directory. This is where you will mount the Amazon FSx file system.

    $ sudo mkdir /mnt/fsx

  5. Create the creds.txt credentials file in the /home/ec2-user directory.

  6. Set the file permissions so that only you (the owner) can read the file by running the following command.

    $ sudo chmod 700 creds.txt
To automatically mount the file system

  1. You automatically mount a file share not joined to your Active Directory by using its private IP address. You can get the file system's private IP address using the Amazon FSx console, on the Network & security tab, in Preferred File Server IP Address.

  2. To automatically mount the file share using its private IP address, add the following line to the /etc/fstab file.

    //file-system-IP-address/file_share /mnt/fsx cifs vers=SMB_version,sec=ntlmsspi,cred=/home/ec2-user/creds.txt,rsize=CIFSMaxBufSize,wsize=CIFSMaxBufSize,cache=none

    Replace CIFSMaxBufSize with the largest value allowed by your kernel. Run the following command to get this value.

    $ modinfo cifs | grep CIFSMaxBufSize
parm:           CIFSMaxBufSize:Network buffer size (not including header). Default: 16384 Range: 8192 to 130048 (uint)

    The output shows that the maximum buffer size is 130048.

  3. Test the fstab entry by using the mount command with the 'fake' option in conjunction with the 'all' and 'verbose' options.

    $ sudo mount -fav
home/ec2-user/fsx      : successfully mounted

  4. To mount the file share, reboot the Amazon EC2 instance.

  5. When the instance is available again, verify that the file system is mounted by running the following command.

    $ sudo mount -l -t cifs
//file-system-IP-address/file_share on /mnt/fsx type cifs (rw,relatime,vers=SMB_version,sec=ntlmsspi,cache=cache_code,username=user1,domain=CORP.EXAMPLE.COM,uid=0,noforceuid,gid=0,noforcegid,addr=192.0.20.0,file_mode=0755,dir_mode=0755,soft,nounix,serverino,mapposix,rsize=1048576,wsize=1048576,echo_interval=60,actimeo=1)

    The line added to the /etc/fstab file in this procedure does the following at the given points:

    • //file-system-IP-address/file_share – Specifies the IP address and share of the Amazon FSx file system you're mounting.

    • /mnt/fsx – Specifies the mount point for the Amazon FSx file system on your EC2 instance.

    • cifs vers=SMB_version – Specifies the type of file system as CIFS and the SMB protocol version. Amazon FSx for Windows File Server supports SMB versions 2.0 through 3.1.1.

    • sec=ntlmsspi – Specifies using NT LAN Manager Security Support Provider Interface to facilitate NTLM challenge-response authentication.

    • cache=cache_mode – Sets the cache mode. This option for CIFS cache can impact performance, and you should test which settings work best (and review Linux documentation) for your kernel and workload. Options strict and none are recommended, because loose can cause data inconsistency due to the looser protocol semantics.

    • cred=/home/ec2-user/creds.txt – Specifies where to get the user credentials.

    • _netdev – Tells the operating system that the file system resides on a device that requires network access. Using this option prevents the instance from mounting the file system until the network service is enabled on the client.

    • 0 – Indicates that the file system should be backed up by dump, if it's a nonzero value. For Amazon FSx, this value should be 0.

    • 0 – Specifies the order in which fsck checks file systems at boot. For Amazon FSx file systems, this value should be 0 to indicate that fsck shouldn't run at start up.