NestJS · Senior · Question 73 of 75

How do you broadcast WebSocket messages across several Nest instances?

1Each instance broadcasts only to its own clients, which is enough
2Run only one instance
✓Correct answer: Use an adapter backed by a shared channel, e.g. the Socket.IO Redis adapter, and configure sticky sessions if the transport needs them

Explanation

A custom IoAdapter subclass can create the Redis adapter and be set with app.useWebSocketAdapter().

Further reading

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