arkatufus / docker-splitter

CLI tool for creating network splits in Docker networks in order to test fault-tolerance.

docker-split

docker-split - Induce a split-brain condition in a cluster created using docker-compose

SYNOPSIS

docker-split CLUSTER NETWORK COMMAND

DESCRIPTION

Create a split-brain condition in the CLUSTER docker cluster inside the NETWORK docker network.

This tool assumes that the docker container names would be in the form of "{CLUSTER}-{NUMBER}"

COMMAND is a string in the form of

<int> [<int>]...] [FROM <int> [<int>]...]

• <int> is the docker container name NUMBER in the "{CLUSTER}-{NUMBER}" pattern.
• If FROM is not omitted, then the listed node(s) will be split from the list of nodes in the FROM section.
• If FROM is omitted, then the listed node(s) will be split from the rest of the nodes in the cluster.

You can chain multiple COMMAND by using AND, example:

1 3 FROM 2 AND 2 FROM 4 AND 3

EXAMPLE

ClusterSplitter cluster docker_default "3"

Splits the node cluster-3 from the rest of the nodes

ClusterSplitter cluster docker_default "3 4 5"

Splits node cluster-3, cluster-4, and cluster-5 from the rest of the nodes, forming their own island of nodes.

ClusterSplitter cluster docker_default "3 FROM 4 5"

Splits the node cluster-3 from cluster-4 and cluster-5

ClusterSplitter cluster docker_default "3 AND 10 FROM 4 5"

Splits the node cluster-3 from the rest of the nodes AND splits the node cluster-10 from node cluster-4 and cluster-5

NOTE

The cluster service WILL NEED to have NET_ADMIN capability enabled inside the docker-compose.yaml file. Example docker-compose.yaml file:

version: '3'

services:
  cluster:
    image: azure.stresstest:0.2.4
    cap_add:
      - NET_ADMIN