CharybdisFS

A remotely controlled fault injection file system.

Create virtualenv using PyEnv

$ pyenv virtualenv 3.8.4 charybdisfs

Install pre-requisites

Ubuntu 20.04

$ sudo apt install build-essential pkg-config libfuse3-dev

CentOS 7

$ sudo yum install fuse3 fuse3-devel

Install Python requirements

$ pyenv local charybdisfs
$ pip install -r requirements.txt

How to build a Docker image

$ docker build -t charybdisfs .

How to run a Docker container

All CharybisFS mounts will be available inside Docker container only.

$ docker run -it --rm --device /dev/fuse --privileged -v $(pwd):/src charybdisfs bash

How to run a Docker container with mount propogation

Whole host filesystem will be available at /docker_host_root and if you mount CharybdisFS at any point under this directory then it'll be available on the host system too.

$ docker run -it --rm --device /dev/fuse --privileged \
    -v $(pwd):/src -v /:/docker_host_root:rw,rshared charybdisfs bash

How to run CharybdisFS for existent directory

The idea behind is to create a bind mount to have access to original files and then mount CharybdisFS to the original path. Note that bind mounts can be done only on the same filesystem.

$ mkdir /path/to/.shadow_source_dir
$ mount --bind /path/to/source_dir /path/to/.shadow_source_dir
$ python -m charybdisfs /path/to/.shadow_source_dir /path/to/source_dir

Unfortunately, you can't use this trick with Docker container mount propogation together.

amoskong/charybdisfs