# Split brain

> A network partition cut a Distributed Erlang cluster in two. Each half kept serving its own clients, and half of the realtime messages never reached the other.

## What happens

A network partition cut a Distributed Erlang cluster in two. Each half kept serving its own clients, and half of the realtime messages never reached the other.

## How to prevent it

Chaos experiments find the partition before it does. A restart rejoins the cluster.

The postmortem opens the first of these that you do not own yet:

- [Chaos engineering](https://wiki.playquorum.dev/research/chaos-engineering.md)

## Components it hits

[Realtime Hub](https://wiki.playquorum.dev/components/ws.md)

## Facts

SEV2 Split brain
- **First Era:** [Series B](https://wiki.playquorum.dev/eras/series-b.md)
- **Starts at:** SEV2
- **Escalates to:** SEV1
- **Lasts:** 1.5 min

## See also

- [Incidents](https://wiki.playquorum.dev/incidents.md)

Source: https://wiki.playquorum.dev/incidents/split-brain