Modifying ARP frames

Hi All,

Is there any way to modify or filter the ARP frames??

thanks!

ARP Handler Inspection may be a good tool, unfortunately I have no knowledge of this product. Why do you want to mess around with ARP anyway ?

Thanks for your reply sysgate.

I have to deal with arp frames because I have a wired LAN configuration. I have a few devices that has the same IP address and it is impossible to be changed. All of them has different MAC address and they take its firmware from a tftp server.

The problem to be solved is the following:

While all the devices are connected to the same switch, and all of them have the same IP address, it has to be possible to upgrade every one (one by one) downloading its firmware from the ftp server.

I was thinking on blocking the tftp arp request to these devices and in some way (e.g. running a script, iptables, etc) when a device tries to connect to the tftp server, the last one automatically adds a fix rule in the arp cache so it does not send an arp request to devices an only response to only one.

Could you pleas help me???