> ## Documentation Index
> Fetch the complete documentation index at: https://docs.thornode.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Quickstart: replay a slot range

> Create a replay key, start a replay job for a recent slot range, and confirm packets reach your UDP receiver.

In about five minutes you will replay a recent slot range into a UDP receiver and watch its packet counter move.

## Before you start

You need:

* An access with **ShredReplay** enabled
* A UDP receiver at a globally routable public IPv4 address, listening on a port from `1024` through `65535`

The [Raw Shred Stream receiver](/products/raw-shred-stream/quickstart#run-the-receiver) works unchanged; both products send raw shred datagrams.

## Start the receiver

```bash theme={null}
SHREDSTREAM_PORT='<udp-port>' node receiver.mjs
```

Leave it running. Open the port through the host firewall, security group, and any NAT forwarding rule.

## Create the key and job

<Steps>
  <Step title="Generate a replay key">
    Open **Endpoints → ShredReplay**, select the access, and generate a
    ShredReplay key. Store it as a secret; it is separate from location tokens.
  </Step>

  <Step title="Choose a slot range">
    Enter start and end slots inside the minimum and maximum the panel shows.
    Refresh the range right before you submit; the window keeps moving.
  </Step>

  <Step title="Enter the receiver">
    Enter the receiver's public IPv4 address and UDP port.
  </Step>

  <Step title="Choose pacing and start">
    Select **Original pacing** for a first run, keep **Speed multiplier** at
    `1`, and start the job.
  </Step>
</Steps>

Watch the receiver:

```text theme={null}
Listening for ShredStream on UDP 20000
packets=0 bytes=0
packets=961 bytes=1184331
```

The job worked when the panel shows it completed and the receiver printed nonzero counts while it ran. Completion means the sender finished the range; UDP delivery is not acknowledged.

## Next steps

* [Understand pacing and job states](/products/shredreplay#choose-pacing)
* [Protect and rotate the replay key](/reference/security)
* [Diagnose UDP delivery](/reference/troubleshooting#raw-shred-stream-or-replay-sends-no-udp-data)