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New Member

disable Arp broadcast

hi all

we are running 3620 router in the lab and we would like to make an arp test to figure things out.

the problem is that everytime we execute "clear arp" cisco send immidatly broadcast to all interfaces and build the arp table, is there anyway to disable that?

the idea is to force the router to use arp request\reply so we'll see the packets with ethereal.

Hall of Fame Super Silver

Re: disable Arp broadcast

I believe that there is not a way to disable the IOS behavior of immediately sending an ARP request when you clear the table. And I do not understand why it would not be enough to see those ARP requests using ethereal, since they are the same requests that IOS would send if it need to find a device.

But having said that I believe there is a way to achieve basically what you want. If you shut down the LAN interface(s) the IOS will clear the ARP entries and will not send out the ARP requests. When you no shut the interface the router will not have the ARP entries and will learn the individual entries as it has need of them.