meshtastic/docs/configuration/module/store-and-forward-module.mdx

---
id: store-and-forward-module
title: Store & Forward Module Settings
sidebar_label: Store & Forward
description: This module allows you to resend text messages after a device has been temporarily not in LoRa range of the mesh.
---

import Tabs from "@theme/Tabs";
import TabItem from "@theme/TabItem";

## Overview

Using this module, a client device can ask a special Store & Forward Server to resend text messages after the client has been temporarily not in LoRa range of the mesh. 
Since firmware version 2.4, when you connect to the Store & Forward Server with a client app, you get the history automatically, which will be much larger than the default cache of around 30 packets on a device.

:::info
Only ESP32 based devices with onboard PSRAM like the T-Beam and T3S3 can be a Store & Forward Server.
:::

When a client device requests the history from the Store & Forward Server, it will resend the text messages over LoRa that it has received. The server will only return messages that are within the time window the client has requested up to the maximum number of messages configured for the server. 
The server does not know which messages the client device actually missed, so it is possible that you receive duplicates. 

:::important
Be mindful when requesting the history, as the server might send a lot of messages which will burden your mesh for a short period of time.
Requesting history over LoRa is not available on the default public channel.
:::

## Details

### How it works

![Store & Forward - Overview](/img/modules/store_and_forward/store_and_forward-overview.webp)

### Requirements

Initial requirements for the Store and Forward Server:

- Store & Forward Servers are intended to be always online. If this module misses any messages, the reliability of the stored messages will be reduced.
- ESP32 Processor based device with onboard PSRAM (T-Beam > v1.0, T3S3, and maybe others).

### Usage Overview

- To use / test this over LoRa you will want at least 3 devices:
  - One ESP32 device with PSRAM configured as `ROUTER` or `store_forward.is_server` set.
  - Two others will be regular clients. If one client sends a text message when the other is not in range, the other can request the history from the server to receive the missed message when it is back in range.

- To use / test this with a client app you will want at least 2 devices:
  - One ESP32 device with PSRAM configured as `ROUTER` or `store_forward.is_server` set.
  - One other device that sends text messages when no app is connected to the Store & Forward Server. When you connect an app to the server, it will automatically retrieve the history.

### Server setup

- Configure your device as a `ROUTER` or set `store_forward.is_server true`.
- Name your server node something that makes it easily identifiable, e.g. "Base Node (S&F)".
- Configure the Store and Forward module

  ```shell title="Required - Enable the module"
  meshtastic --set store_forward.enabled true
  ```

  ```shell title="Optional - Disable sending heartbeat."
  meshtastic --set store_forward.heartbeat false
  ```

  :::tip
  Best to disable the heartbeat (which is sent every 15 minutes) to reduce network traffic if you only want to retrieve it by connecting with an app to the server, or when all client devices have identified the server.
  :::

### Client Usage

Currently implemented in the Android and Apple apps version 2.2.23 and higher. To request the history from the Store & Forward Server, for Android it is required to send it a direct message containing the text "SF" (without quotes). The server will then respond with the requested messages.
The Apple apps will also show whether a node is a Store & Forward Server in the node list after it heard the heartbeat. You can then long press the node and select "Client History" to request the history from the server.

Since 2.4, when connecting to the Store & Forward Server itself, the text message history will be automatically retrieved and displayed in the app.

## Settings

### Enabled

Enables the module.

### Heartbeat

The Store & Forward Server sends a periodic message onto the network. This allows connected devices to know that a server is in range and listening to received messages. A client like Android, iOS, or Web can (if supported) indicate to the user whether a Store & Forward Server is available.

### History Return Max

Sets the maximum number of messages to return to a client device when it requests the history.

### History Return Window

Limits the time period (in minutes) a client device can request.

### Records

Set this to the maximum number of records the server will save. Best to leave this at the default (`0`) where the module will use 2/3 of your device's available PSRAM. This is about 11,000 records.

### Is server

Set to true to configure your node with PSRAM as a Store & Forward Server for storing and forwarding messages. This is an alternative to setting the node as a `ROUTER` and only available since 2.4.

## Store & Forward Module Config Client Availability

<Tabs
groupId="settings"
defaultValue="cli"
values={[
{label: 'Android', value: 'android'},
{label: 'Apple', value: 'apple'},
{label: 'CLI', value: 'cli'},
{label: 'Web', value: 'web'},
]}>

<TabItem value="android">

#### Android

:::info
Store and Forward Config options are available for Android.

1. Open the Meshtastic App
2. Navigate to: **Vertical Ellipsis (3 dots top right) > Radio Configuration > Store & Forward**
:::

</TabItem>

<TabItem value="apple">

#### Apple

:::info
All Store & Forward module config options are available on iOS, iPadOS and macOS at Settings > Module Configuration > Store & Forward.
:::

</TabItem>

<TabItem value="cli">

#### CLI

|               Setting               | Acceptable Values | Default |
| :---------------------------------: | :---------------: | :-----: |
|        store_forward.enabled        |  `true`, `false`  | `false` |
|       store_forward.heartbeat       |  `true`, `false`  | `false` |
|  store_forward.history_return_max   |     `integer`     |   `0` (25 messages)  |
| store_forward.history_return_window |     `integer`     |   `0` (240 minutes)  |
|        store_forward.records        |     `integer`     |   `0` (≈11,000 records) |
|        store_forward.is_server      |  `true`, `false`  | `false` |

:::tip

Because the device will reboot after each command is sent via CLI, it is recommended when setting multiple values in a config section that commands be chained together as one.

```shell title="Example:"
meshtastic --set store_forward.enabled true --set store_forward.history_return_max 0
```

:::

##### Examples of CLI Usage

```shell title="Enable the module"
meshtastic --set store_forward.enabled true
```

```shell title="Disable the module"
meshtastic --set store_forward.enabled false
```

```shell title="Set node as server"
meshtastic --set store_forward.is_server true
```

```shell title="Set store_forward.heartbeat to default"
meshtastic --set store_forward.heartbeat 0
```


```shell title="Set store_forward.history_return_max to default (25 messages)"
meshtastic --set store_forward.history_return_max 0
```
```shell title="Set store_forward.history_return_max to 100 messages"
meshtastic --set store_forward.history_return_max 100
```

```shell title="Set store_forward.history_return_window to default (240 minutes)"
meshtastic --set store_forward.history_return_window 0
```
```shell title="Set store_forward.history_return_window to 1 day (1440 minutes)"
meshtastic --set store_forward.history_return_window 1440
```

```shell title="Set store_forward.records to default (≈11,000 records)"
meshtastic --set store_forward.records 0
```
```shell title="Set store_forward.records to 100 records"
meshtastic --set store_forward.records 100
```
</TabItem>


<TabItem value="web">

#### Web

:::info
All Store & Forward module config options are available in the Web UI at Config > Module Config > S&F.
:::

</TabItem>
</Tabs>