A gratuitous ARP (Address Resolution Protocol) request is a broadcast message used to update the ARP caches of other devices on the same network segment. This type of ARP request is typically used to update the ARP caches after changing the IP address of a network device, or to prevent ARP cache poisoning attacks.
To send a gratuitous ARP request in Linux, you can use the arping utility. The arping utility allows you to send an ARP request and receive a response, which can be used to update the ARP caches of other devices on the network.
Here’s how to send a gratuitous ARP request using the arping utility:
- Open a terminal window.
- Type the following command to send a gratuitous ARP request, replacing “ip_address” with the desired IP address:
arping -U -c 1 ip_address
The -U option is used to send a gratuitous ARP request, and the -c 1 option is used to specify that only one ARP request should be sent.
- The gratuitous ARP request should be broadcast to other devices on the network, updating their ARP caches with the new information.
Note that the arping utility must be installed on your system in order to use it. On some systems, you may need to install the iputils-arping package in order to use the arping utility.