README.md

efs-utils

Utilities for Amazon Elastic File System (EFS)

The efs-utils package has been verified against the following Linux distributions:

Distribution	Package Type	init System
Amazon Linux 2017.09	rpm	upstart
Amazon Linux 2	rpm	systemd
CentOS 7	rpm	systemd
CentOS 8	rpm	systemd
RHEL 7	rpm	systemd
RHEL 8	rpm	systemd
Fedora 28	rpm	systemd
Fedora 29	rpm	systemd
Fedora 30	rpm	systemd
Fedora 31	rpm	systemd
Fedora 32	rpm	systemd
Debian 9	deb	systemd
Debian 10	deb	systemd
Ubuntu 16.04	deb	systemd
Ubuntu 18.04	deb	systemd
Ubuntu 20.04	deb	systemd
OpenSUSE Leap	rpm	systemd
OpenSUSE Tumbleweed	rpm	systemd
SLES 12	rpm	systemd
SLES 15	rpm	systemd

The efs-utils package has been verified against the following MacOS distributions:

Distribution	init System
MacOS Big Sur	launchd
MacOS Monterey	launchd
MacOS Ventura	launchd

README contents

• Prerequisites
• Optional
• Installation
  • On Amazon Linux distributions
  • Install via AWS Systems Manager Distributor
  • On other Linux distributions
  • On MacOS Big Sur and macOS Monterey distribution
    • Run tests
• Usage
  • mount.efs
  • MacOS
  • amazon-efs-mount-watchdog
• Troubleshooting
• Upgrading stunnel for RHEL/CentOS
• Upgrading stunnel for SLES12
• Upgrading stunnel for MacOS
• Install botocore
  • RPM
  • DEB
  • On Debian10 and Ubuntu20, the botocore needs to be installed in specific target folder
  • To install botocore on MacOS
• Upgrade botocore
• Enable mount success/failure notification via CloudWatch log
  • Step 1. Install botocore
  • Step 2. Enable CloudWatch log feature in efs-utils config file /etc/amazon/efs/efs-utils.conf
  • Step 3. Attach the CloudWatch logs policy to the IAM role attached to instance.
• Optimize readahead max window size on Linux 5.4+
• Using botocore to retrieve mount target ip address when dns name cannot be resolved
  • Step 1. Install botocore
  • Step 2. Allow DescribeMountTargets and DescribeAvailabilityZones action in the IAM policy
• The way to access instance metadata
• Use the assumed profile credentials for IAM
• Enabling FIPS Mode
• License Summary

Prerequisites

• nfs-utils (RHEL/CentOS/Amazon Linux/Fedora) or nfs-common (Debian/Ubuntu)
• OpenSSL 1.0.2+
• Python 3.4+
• stunnel 4.56+

Optional

• botocore 1.12.0+

Installation

On Amazon Linux distributions

For those using Amazon Linux or Amazon Linux 2, the easiest way to install efs-utils is from Amazon's repositories:

$ sudo yum -y install amazon-efs-utils

Install via AWS Systems Manager Distributor

You can now use AWS Systems Manage Distributor to automatically install or update amazon-efs-utils. Please refer to Using AWS Systems Manager to automatically install or update Amazon EFS clients for more guidance.

The following are prerequisites for using AWS Systems Manager Distributor to install or update amazon-efs-utils:

1. AWS Systems Manager agent is installed on the distribution (For Amazon Linux and Ubuntu, AWS Systems Manager agent is pre-installed, for other distributions, please refer to install AWS Systems Manager agent on Linux EC2 instance for more guidance.)

2. Instance is attached with IAM role with AWS managed policy AmazonElasticFileSystemsUtils, this policy will enable your instance to be managed by AWS Systems Manager agent, also it contains permissions to support specific features.

On other Linux distributions

Other distributions require building the package from source and installing it.

• To build and install an RPM:

If the distribution is not OpenSUSE or SLES

$ sudo yum -y install git rpm-build make
$ git clone https://github.com/aws/efs-utils
$ cd efs-utils
$ make rpm
$ sudo yum -y install build/amazon-efs-utils*rpm

Otherwise

$ sudo zypper refresh
$ sudo zypper install -y git rpm-build make
$ git clone https://github.com/aws/efs-utils
$ cd efs-utils
$ make rpm
$ sudo zypper --no-gpg-checks install -y build/amazon-efs-utils*rpm

On OpenSUSE, if you see error like File './suse/noarch/bash-completion-2.11-2.1.noarch.rpm' not found on medium 'http://download.opensuse.org/tumbleweed/repo/oss/' during installation of git, run the following commands to re-add repo OSS and NON-OSS, then run the install script above again.

sudo zypper ar -f -n OSS http://download.opensuse.org/tumbleweed/repo/oss/ OSS
sudo zypper ar -f -n NON-OSS http://download.opensuse.org/tumbleweed/repo/non-oss/ NON-OSS
sudo zypper refresh

• To build and install a Debian package:

$ sudo apt-get update
$ sudo apt-get -y install git binutils
$ git clone https://github.com/aws/efs-utils
$ cd efs-utils
$ ./build-deb.sh
$ sudo apt-get -y install ./build/amazon-efs-utils*deb

On macOS Big Sur, macOS Monterey, and macOS Ventura distributions

For EC2 Mac instances running macOS Big Sur, macOS Monterey and macOS Ventura, you can install amazon-efs-utils from the homebrew-aws respository. Note that this will ONLY work on EC2 instances running macOS Big Sur and macOS Monterey, not local Mac computers.

brew install amazon-efs-utils

This will install amazon-efs-utils on your EC2 Mac Instance in the directory /usr/local/Cellar/amazon-efs-utils. At the end of the installation, it will print a set of commands that must be executed in order to start using efs-utils. The instructions that are printed after amazon-efs-utils and must be executed are:

# Perform below actions to start using efs:
    sudo mkdir -p /Library/Filesystems/efs.fs/Contents/Resources
    sudo ln -s /usr/local/bin/mount.efs /Library/Filesystems/efs.fs/Contents/Resources/mount_efs

# Perform below actions to stop using efs:
    sudo rm /Library/Filesystems/efs.fs/Contents/Resources/mount_efs

# To enable watchdog for using TLS mounts:
    sudo cp /usr/local/Cellar/amazon-efs-utils/<version>/libexec/amazon-efs-mount-watchdog.plist /Library/LaunchAgents
    sudo launchctl load /Library/LaunchAgents/amazon-efs-mount-watchdog.plist

# To disable watchdog for using TLS mounts:
    sudo launchctl unload /Library/LaunchAgents/amazon-efs-mount-watchdog.plist

Run tests

• Set up a virtualenv for efs-utils

$ virtualenv ~/.envs/efs-utils
$ source ~/.envs/efs-utils/bin/activate
$ pip install -r requirements.txt

• Run tests

$ make test

Usage

mount.efs

efs-utils includes a mount helper utility to simplify mounting and using EFS file systems.

To mount with the recommended default options, simply run:

$ sudo mount -t efs file-system-id efs-mount-point/

To mount file system to a specific mount target of the file system, run:

$ sudo mount -t efs -o mounttargetip=mount-target-ip-address file-system-id efs-mount-point/

To mount file system within a given network namespace, run:

$ sudo mount -t efs -o netns=netns-path file-system-id efs-mount-point/

To mount file system to the mount target in specific availability zone (e.g. us-east-1a), run:

$ sudo mount -t efs -o az=az-name file-system-id efs-mount-point/

To mount over TLS, simply add the tls option:

$ sudo mount -t efs -o tls file-system-id efs-mount-point/

To authenticate with EFS using the system’s IAM identity, add the iam option. This option requires the tls option.

$ sudo mount -t efs -o tls,iam file-system-id efs-mount-point/

To mount using an access point, use the accesspoint= option. This option requires the tls option. The access point must be in the "available" state before it can be used to mount EFS.

$ sudo mount -t efs -o tls,accesspoint=access-point-id file-system-id efs-mount-point/

To mount your file system automatically with any of the options above, you can add entries to /efs/fstab like:

file-system-id efs-mount-point efs _netdev,tls,iam,accesspoint=access-point-id 0 0

For more information on mounting with the mount helper, see the manual page:

man mount.efs

or refer to the documentation.

MacOS

For EC2 instances using Mac distribution, the recommended default options will perform a tls mount:

$ sudo mount -t efs file-system-id efs-mount-point/

or

$ sudo mount -t efs -o tls file-system-id efs-mount-point/

To mount without TLS, simply add the notls option:

$ sudo mount -t efs -o notls file-system-id efs-mount-point/

amazon-efs-mount-watchdog

efs-utils contains a watchdog process to monitor the health of TLS mounts. This process is managed by either upstart or systemd depending on your Linux distribution and launchd on Mac distribution, and is started automatically the first time an EFS file system is mounted over TLS.

Troubleshooting

If you run into a problem with efs-utils, please open an issue in this repository. We can more easily assist you if relevant logs are provided. You can find the log file at /var/log/amazon/efs/mount.log.

Often times, enabling debug level logging can help us find problems more easily. To do this, run
sed -i '/logging_level = INFO/s//logging_level = DEBUG/g' /etc/amazon/efs/efs-utils.conf.

You can also enable stunnel debug logs with
sed -i '/stunnel_debug_enabled = false/s//stunnel_debug_enabled = true/g' /etc/amazon/efs/efs-utils.conf.

Make sure to perform the failed mount again after running the prior commands before pulling the logs.

Upgrading stunnel for RHEL/CentOS

By default, when using the EFS mount helper with TLS, it enforces certificate hostname checking. The EFS mount helper uses the stunnel program for its TLS functionality. Please note that some versions of Linux do not include a version of stunnel that supports TLS features by default. When using such a Linux version, mounting an EFS file system using TLS will fail.

Once you’ve installed the amazon-efs-utils package, to upgrade your system’s version of stunnel, see Upgrading Stunnel.

Upgrading stunnel for SLES12

Run the following commands and follow the output hint of zypper package manager to upgrade the stunnel on your SLES12 instance

sudo zypper addrepo https://download.opensuse.org/repositories/security:Stunnel/SLE_12_SP5/security:Stunnel.repo
sudo zypper refresh
sudo zypper install -y stunnel

Upgrading stunnel for MacOS

The installation installs latest stunnel available in brew repository. You can also upgrade the version of stunnel on your instance using the command below:

brew upgrade stunnel

Install botocore

efs-utils uses botocore to interact with other AWS services. Please note the package type from the above table and install botocore based on that info. If botocore is already installed and does not meet the minimum required version, you can upgrade the botocore by following the upgrade botocore section.

• Download the get-pip.py script

RPM

sudo yum -y install wget

if [[ "$(python3 -V 2>&1)" =~ ^(Python 3.6.*) ]]; then
    sudo wget https://bootstrap.pypa.io/pip/3.6/get-pip.py -O /tmp/get-pip.py
elif [[ "$(python3 -V 2>&1)" =~ ^(Python 3.5.*) ]]; then
    sudo wget https://bootstrap.pypa.io/pip/3.5/get-pip.py -O /tmp/get-pip.py
elif [[ "$(python3 -V 2>&1)" =~ ^(Python 3.4.*) ]]; then
    sudo wget https://bootstrap.pypa.io/pip/3.4/get-pip.py -O /tmp/get-pip.py
else
    sudo wget https://bootstrap.pypa.io/get-pip.py -O /tmp/get-pip.py
fi

DEB

sudo apt-get update
sudo apt-get -y install wget

if echo $(python3 -V 2>&1) | grep -e "Python 3.6"; then
    sudo wget https://bootstrap.pypa.io/pip/3.6/get-pip.py -O /tmp/get-pip.py
elif echo $(python3 -V 2>&1) | grep -e "Python 3.5"; then
    sudo wget https://bootstrap.pypa.io/pip/3.5/get-pip.py -O /tmp/get-pip.py
elif echo $(python3 -V 2>&1) | grep -e "Python 3.4"; then
    sudo wget https://bootstrap.pypa.io/pip/3.4/get-pip.py -O /tmp/get-pip.py
else
    sudo apt-get -y install python3-distutils
    sudo wget https://bootstrap.pypa.io/get-pip.py -O /tmp/get-pip.py
fi

• To install botocore on RPM

sudo python3 /tmp/get-pip.py
sudo pip3 install botocore || sudo /usr/local/bin/pip3 install botocore

• To install botocore on DEB

sudo python3 /tmp/get-pip.py
sudo pip3 install botocore || sudo /usr/local/bin/pip3 install botocore

On Debian10 and Ubuntu20, the botocore needs to be installed in specific target folder

sudo python3 /tmp/get-pip.py
sudo pip3 install --target /usr/lib/python3/dist-packages botocore || sudo /usr/local/bin/pip3 install --target /usr/lib/python3/dist-packages botocore

To install botocore on MacOS

sudo pip3 install botocore

Upgrade botocore

Pass --upgrade to the corresponding installation scripts above based on system platform and distribution

sudo pip3 install botocore --upgrade

Enable mount success/failure notification via CloudWatch log

efs-utils now support publishing mount success/failure logs to CloudWatch log. By default, this feature is disabled. There are three steps you must follow to enable and use this feature:

Step 1. Install botocore

Follow install botocore section

Step 2. Enable CloudWatch log feature in efs-utils config file /etc/amazon/efs/efs-utils.conf

sudo sed -i -e '/\[cloudwatch-log\]/{N;s/# enabled = true/enabled = true/}' /etc/amazon/efs/efs-utils.conf

• For MacOS:

sudo sed -i -e '/\[cloudwatch-log\]/{N;s/# enabled = true/enabled = true/;}' /usr/local/Cellar/amazon-efs-utils/<version>/libexec/etc/amazon/efs/efs-utils.conf

You can also configure CloudWatch log group name and log retention days in the config file. If you want to have separate log groups in Cloudwatch for every mounted file system, add /{fs_id} to the end of the log_group_name field in efs-utils.conf file. For example, the log_group_name in efs-utils.conf file would look something like:

[cloudwatch-log]
log_group_name = /aws/efs/utils/{fs_id}

Step 3. Attach the CloudWatch logs policy to the IAM role attached to instance.

Attach AWS managed policy AmazonElasticFileSystemsUtils to the iam role you attached to the instance, or the aws credentials configured on your instance.

After completing the three prerequisite steps, you will be able to see mount status notifications in CloudWatch Logs.

Optimize readahead max window size on Linux 5.4+

A change in the Linux kernel 5.4+ results a throughput regression on NFS client. With patch, starting from 5.4.*, Kernels containing this patch now set the default read_ahead_kb size to 128 KB instead of the previous 15 MB. This read_ahead_kb is used by the Linux kernel to optimize performance on NFS read requests by defining the maximum amount of data an NFS client can pre-fetch in a read call. With the reduced value, an NFS client has to make more read calls to the file system, resulting in reduced performance.

To avoid above throughput regression, efs-utils will modify read_ahead_kb to 15 * rsize (could be configured via mount option, 1MB by default) after mount success on Linux 5.4+. (not support on MacOS)

This optimization will be enabled by default. To disable this optimization:

sed -i "s/optimize_readahead = false/optimize_readahead = true/" /etc/amazon/efs/efs-utils.conf

To re-enable this optimization

sed -i "s/optimize_readahead = true/optimize_readahead = false/" /etc/amazon/efs/efs-utils.conf

You can mount file system with a given rsize, run:

$ sudo mount -t efs -o rsize=rsize-value-in-bytes file-system-id efs-mount-point/

You can also manually chose a value of read_ahead_kb to optimize read throughput on Linux 5.4+ after mount.

$ sudo bash -c "echo read-ahead-value-in-kb > /sys/class/bdi/0:$(stat -c '%d' efs-mount-point)/read_ahead_kb"

Using botocore to retrieve mount target ip address when dns name cannot be resolved

efs-utils now supports using botocore to retrieve mount target ip address when dns name cannot be resolved, e.g. when user is mounting a file system in another VPC. There are two prerequisites to use this feature:

Step 1. Install botocore

Follow install botocore section

Step 2. Allow DescribeMountTargets and DescribeAvailabilityZones action in the IAM policy

Allow the elasticfilesystem:DescribeMountTargets and ec2:DescribeAvailabilityZones action in your policy attached to the iam role you attached to the instance, or the aws credentials configured on your instance. We recommend you attach AWS managed policy AmazonElasticFileSystemsUtils.

This feature will be enabled by default. To disable this feature:

sed -i "s/fall_back_to_mount_target_ip_address_enabled = true/fall_back_to_mount_target_ip_address_enabled = false/" /etc/amazon/efs/efs-utils.conf

If you decide that you do not want to use this feature, but need to mount a cross-VPC file system, you can use the mounttargetip option to do so, using the desired mount target ip address in the mount command.

The way to access instance metadata

efs-utils by default uses IMDSv2, which is a session-oriented method used to access instance metadata. If you don't want to use IMDSv2, you can disable the token fetching feature by running the following command:

sed -i "s/disable_fetch_ec2_metadata_token = false/disable_fetch_ec2_metadata_token = true/" /etc/amazon/efs/efs-utils.conf

Use the assumed profile credentials for IAM

To authenticate with EFS using the system’s IAM identity of an awsprofile, add the iam option and pass the profile name to awsprofile option. These options require the tls option.

$ sudo mount -t efs -o tls,iam,awsprofile=test-profile file-system-id efs-mount-point/

To configure the named profile, see the Named Profiles doc and Support Config File Settings doc for more details. If the credentials (e.g. aws_access_key_id) are not configured in /root/.aws/credentials or /root/.aws/config (note that the path prefix may vary based on the root path of sudo), efs-utils will use botocore to assume the named profile. This will require botocore is pre-installed, please follow install botocore section to install botocore first.

Normally you will need to configure your profile IAM policy to make the assume works. For example, if you want to perform a cross-account mounting, suppose you have established vpc-peering-connections between your vpcs, next step you need to do is giving permission to account B so that it can assume a role in account A and then mount the file system that belongs to account A. You can see IAM doc for more details.

After the IAM identity is setup, you can configure your awsprofile credentials or config. You can refer to sdk settings. For example you can define the profile to use the credentials of profile default to assume role in account A by defining the source_profile.

# /root/.aws/credentials
[default]
aws_access_key_id = AKIAIOSFODNN7EXAMPLE
aws_secret_access_key_id =wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY

# /root/.aws/config
[default]
...

[profile test-profile]
role_arn = <role-arn-in-account-A>
source_profile = default

Or you can use the credentials from IAM role attached to instance to assume the named profile, e.g.

# /root/.aws/config
[profile test-profile]
role_arn = <role-arn-in-account-A>
credential_source = Ec2InstanceMetadata

Enabling FIPS Mode

Efs-Utils is able to enter FIPS mode when mounting your file system. To enable FIPS you need to modify the EFS-Utils config file:

sed -i "s/fips_mode_enabled = false/fips_mode_enabled = true/" /etc/amazon/efs/efs-utils.conf

This will enable any potential API call from EFS-Utils to use FIPS endpoints and cause stunnel to enter FIPS mode

Note: FIPS mode requires that the installed version of OpenSSL is compiled with FIPS.

To verify that the installed version is compiled with FIPS, look for OpenSSL X.X.Xx-fips in the stunnel -version command output e.g.

$ stunnel -version
stunnel 4.56 on x86_64-koji-linux-gnu platform
Compiled/running with OpenSSL 1.0.2k-fips  26 Jan 2017
Threading:PTHREAD Sockets:POLL,IPv6 SSL:ENGINE,OCSP,FIPS Auth:LIBWRAP

For more information on how to configure OpenSSL with FIPS see the OpenSSL FIPS README.

License Summary

This code is made available under the MIT license.