I believe they call this a Gratuitous ARP Request. It is used automatically when interfaces are brought up to detect IP conflicts.
On 6/17/10 5:45 PM, Chris Woodfield wrote: > Looks like all the replies I got were private, so thanks all - to summarize, > I got everything from "Read The Fine Kernel Source" to "Read The Fine RFC" to > "Read RFC 1122, Section 2.3.2.1, it's quite a Fine read". > > So for other folks out there like me who obviously can't read RFCs, the > answer is "yes". :) > > -C > > On Jun 16, 2010, at 3:57 51PM, Chris Woodfield wrote: > > >> OK, this sounds Really Wacky (or, Really Hacky if you're into puns) but >> there's a reason for it, I swear... >> >> Will typical OSS UNIX kernels (Linux, BSD, MacOS X, etc) reply to a crafted >> ARP request that, instead of having FF:FF:FF:FF:FF:FF as its destination MAC >> address, is instead sent to the already-known unicast MAC address of the >> host? >> >> Next, what would be your utility of choice for crafting such a packet? Or is >> this something one would need to code up by hand in a lower-level language? >> >> Thanks, >> >> -C >> > > -- Steve King Senior Linux Engineer - Advance Internet, Inc. Cisco Certified Network Associate CompTIA Linux+ Certified Professional CompTIA A+ Certified Professional
