> For the complete documentation index, see [llms.txt](https://courier-gojek.gitbook.io/vernemq/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://courier-gojek.gitbook.io/vernemq/configuring-vernemq/messagepassing.md).

# Redis based message passing

New message passing model for VerneMQ

This new model uses redis as its queue for passing the messages between the broker nodes. Each broker node has a set of workers which constantly polls redis to fetch messages from its own queue, called main queue.

### Redis shards connect options

Specify the list of comma separated connect options list \[\[{host, "localhost"}, {port, 1234}]] of redis shards used for message passing.

```
msg_queue_redis_shards_connect_options = [[{host,"127.0.0.1"},{port,6379},{database,1}]]
```

### Main queue workers per redis shard

Specify the number of worker processes per redis shard that will poll their main queues in message passing redis shard for new messages.

```
main_queue_workers_per_redis_shard = 1
```

### Main queue worker sleep interval

Specify the interval (in milliseconds) a worker process waits before making another poll request.

```
redis_queue_sleep_interval = 0
```