# ip arp-scan

## Syntax

```
[no] ip arp-scan off|on
```

## Syntax Description

<table><thead><tr><th width="203">Keyword</th><th>Description</th></tr></thead><tbody><tr><td><code>no</code></td><td>(Optional) This is the same as <code>ip arp-scan off.</code></td></tr><tr><td><code>off</code></td><td>Disables ARP scanning.</td></tr><tr><td><code>on</code></td><td>Enables ARP scanning.</td></tr></tbody></table>

## Defaults

ARP scanning is enabled on LAN interfaces but disabled on WAN interfaces by default.&#x20;

## Usage Guidelines

When ARP scanning is enabled on an Interface, Island will periodically send ARP requests to every valid IP address on the interface network. This allows Island to discover all devices on the network, even those that are not otherwise sending any traffic through the Island.

This command is valid only in interface context. Entering it will set the [interface mode](https://docs.islandrouter.com/island-router-cli-2.3.2/commands/ip-interface-context/ip-autoconfig) to `manual`.

## Examples

```
ip arp-scan off
```

## Related Commands

{% content-ref url="../interface" %}
[interface](https://docs.islandrouter.com/island-router-cli-2.3.2/commands/interface)
{% endcontent-ref %}

{% content-ref url="ip-autoconfig" %}
[ip-autoconfig](https://docs.islandrouter.com/island-router-cli-2.3.2/commands/ip-interface-context/ip-autoconfig)
{% endcontent-ref %}