arpsend - utility to send ARP requests.
arpsend < -U -i source_ip
  | -D  -e target_ip
  [-e target_ip] ... > [-c count]
  [-w timeout] interface
Utility arpsend sends ARP packets on device interface to detect or
  update neighbours' ARP caches with a given IP.
Run utility with one of the following commands:
  - -D
- Send broadcast ARP request to detect neighbours with target_ip. You
      have to specify target_ip (-e option).
- -U
- Send broadcast ARP request to update neighbours' ARP caches with
      source_ip. You have to specify source_ip (-i
    option).
  - -c count
- Number of packets to send. Default is infinity.
- -w interval
- Interval between packets, in seconds. Default is 1 second.
- -i source_ip_address
- Set source IP address field in ARP packet.
- -e target_ip_address
- Set target IP address field in ARP packet. Note that you can specify
      -e option multiple times to detect many IP addresses in one utility
      call.
arpsend returns 0 upon successful execution. If something goes wrong, it
  returns an appropriate error code.
  - 1	EXC_USAGE
- Usage error
- 2	EXC_SYSTEM
- System error
- 3	EXC_RECV
- ARP reply was received
To send request on interface eth0 to detect any neighbour computers with
  IP 192.168.10.200:
	arpsend -D -e 192.168.10.200 eth0
To send request on interface eth0 to update neighbours' ARP
    caches with IP 192.168.10.200:
  
  	arpsend -U -i 192.168.10.200 eth0
Interface you use have to be arpable and not be loopback (i.e. /sbin/ip link
  show interface should show neither NOARP not LOOPBACK
  flags in interface parameters).
Copyright (C) 2000-2007, SWsoft. Licensed under GNU GPL.