core-extra/docs/docker.md

# Docker Node Support

## Overview

Provided below is some information for helping setup and use Docker
nodes within a CORE scenario.

## Installation

### Debian Systems

```shell
sudo apt install docker.io
```

### RHEL Systems

## Configuration

Custom configuration required to avoid iptable rules being added and removing
the need for the default docker network, since core will be orchestrating
connections between nodes.

Place the file below in **/etc/docker/docker.json**

```json
{
  "bridge": "none",
  "iptables": false
}
```

## Group Setup

To use Docker nodes within the python GUI, you will need to make sure the
user running the GUI is a member of the docker group.

```shell
# add group if does not exist
sudo groupadd docker

# add user to group
sudo usermod -aG docker $USER

# to get this change to take effect, log out and back in or run the following
newgrp docker
```

## Image Requirements

Images used by Docker nodes in CORE need to have networking tools installed for
CORE to automate setup and configuration of the network within the container.

Example Dockerfile:

```
FROM ubuntu:latest
RUN apt-get update
RUN apt-get install -y iproute2 ethtool
```

Build image:

```shell
sudo docker build -t <name> .
```

## Tools and Versions Tested With

* Docker version 18.09.5, build e8ff056
* nsenter from util-linux 2.31.1