Let’s say you have a Microsoft® Windows® “Server” instance in AWS EC2 and you would like to get a large tree of directories and thousands of files off the local NFTS filesystem and into an AWS EFS Access Point. The easiest approach would be to create a tarball and drop it into S3 for processing by a Linux host that is already connected to EFS.

But what if you’d like to keep the filesystem in sync as little changes are made to the files trapped on Microsoft® Windows®? One option is to mount EFS in Windows® Subsystem for Linux® and periodically run rsync.

Unless you have the “metal” flavor of AWS EC2 instance, you will need to run the old WSL v1; the virutalization features required by WSL v2 are not offered by AWS. See the installation instructions, or blindly follow my procedure by pasting the following into MS-DOS running as a really real Administrator, i.e. not the SSM user:

wsl --install --enable-wsl1 --no-launch
shutdown -r
wsl --set-default-version 1
wsl --install --distribution ubuntu

It doesn’t much matter what the non-root username is; I use ec2-user following the AWS convention. Within the Ubuntu installation in WSL, install unzip, then execute the standard AWS CLI installation instructions:

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install unzip nfs-common
cd $(mktemp -d)
curl "https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip" -o awscliv2.zip
unzip -q awscliv2.zip
sudo ./aws/install

Microsoft® Windows® may crash when installing the AWS CLI. If it does, try to reconnect after a reboot.

Then build and install the efs-utils package:

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
. "$HOME/.cargo/env"

sudo apt-get install git binutils rustc cargo pkg-config libssl-dev
mkdir -p "$HOME/aws-busy-work/efs-utils"
cd "$HOME/aws-busy-work/efs-utils"
git clone https://github.com/aws/efs-utils.git .
./build-deb.sh
mv ./build/amazon-efs-utils*deb /tmp/
sudo apt-get -y install /tmp/amazon-efs-utils*deb

It’s common for Microsoft® Windows® to crash when cloning the repository from Microsoft® GitHub®, because Microsoft® Windows® has stability issues. Prepare to mount an EFS Access Point

efs_fs_id=fs-1234567890abcdef
efs_ap_id=fsap-1234567890abcdef
mount_point=content

cd $HOME
mkdir -p $mount_point
sudo mount -t efs -o tls,iam,accesspoint=$ $: $mount_point

If Microsoft® Windows® reboots from the crash, try copying files to the mounted EFS Access Point.