Cisco – Gratuitous ARP: Disabling / Blocking / Ignoring / Spoofing

Send, clear, ignore and spoof ARP. Know how to truly disable the processing of gratuitous ARP in a Cisco router.

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DHCP – BAD_ADDRESS entries caused by IP Device Tracking

Microsoft Windows has a feature that detects IP conflicts.  A Cisco switch can effectively turn that feature into a DoS attack on your DHCP server.  That’s pretty neat.

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