Before Docker was a thing...

LXC Tricks

Small bash script that manages LXC containers, performs operations on one of the containers or all configured containers at once.

Prerequisites

All active containers should have:

1. User with name same as container name - sh command assumes that all containers have user with the same name as container name. Sh commands are performed as this user.
2. Running ssh server - cp command uses scp program to perform transfers between containers.

Installation

Simply download the script and make it an executable file.

BIN_DIR=~/bin # change this if you want
mkdir -p $BIN_DIR
wget https://github.com/muroc/lxc-tricks/raw/master/container \
  -O $BIN_DIR/container
chmod +x $BIN_DIR/container

If BIN_DIR is no on the PATH, modify PATH in rc file of your shell.

RC_FILE=~/.bashrc # change if you are not using bash
echo "PATH=$BIN_DIR:$PATH" >> $RC_FILE
. $RC_FILE

Configuration

Each managed container needs configuration file at location ~/.c/${CONTAINER_NAME}. Configuration file may be empty.

Following command creates empty configuration files for all lxc containers.

mkdir -p ~/.c
for C in `lxc-ls`; do touch ~/.c/$C; done

If no configuration files are present, the script will print warning message and manage all available lxc containers.

Usage

The basics

container help # prints detailed usage information
container start # starts all active containers
container browser start # starts container of name browser
container browser sh # starts shell in container browser as user browser
container browser # same as above sh is the default action
container browser sudo # starts root shell in container browser

Copying files between containers

Following command copies file /home/browser/Downloads/photo.jpg from container browser to container gamedev at location /home/gamedev/photo.jpg:

container cp browser:Downloads/photo.jpg gamedev:

Transfer is done using scp program, so ssh servers running on the containers are needed to perform the transfer.

Container symlinks

Name of the container can be read from program name (busybox-like behavior). Creating symlink for each container shortens each command by 10 characters.

Following script creates symlink for container named browser:

BIN_DIR=~/bin
cd $BIN_DIR
ln -s container browser

Now we can operate on this container through symlink:

browser start
browser firefox https://github.com/muroc/lxc-tricks
browser stop

Contribution

Push requests are very welcome.

TODO

• default USERNAME configuration for sh command
• per-container username configuration for sh command to remove username prerequisite
• per-container FORCE_TERMINAL configuration
• cp command based on lxc-usernsexec to remove ssh prerequisite
• Background section before Prerequisites
• gif-animated usage at the top of README.md file