Maybe, I'm not completely understanding this, but from my own testing, it seems to me that, when I do this without regard to ip directed broadcast, I get one response back from the closest interface, but perhaps they are using source routing or something to cause this? In message <19970730211625.11611@texas.net>, Edward Henigin writes:
this does work as you'd expect (it prevents the cisco from framing an IP broadcast packet into an ethernet broadcast frame) BUT unfortunately it can break Windows networking, as well as BOOTP/DHCP, depending on how you're set up.
but if you're not using one of the above (routed), then by all means, 'no ip directed-broadcast' is an excellent way to go..
-- On Wed, Jul 30, 1997 at 02:52:14PM -0700, Craig A. Huegen said:
On Wed, 30 Jul 1997, Jeffrey S. Curtis wrote:
==>(And to answer the proverbial "how do I configure my router for that" ==>in advance, the answer is that, at least on my boxes, the not-allowing- ==>broadcast-pings-through-as-broadcasts-onto-the-target-media thing is on ==>by default. Source address filtering, however, is not.)
For Ciscos, "no ip directed-broadcast" on your interfaces will prevent remote devices from sending directed broadcasts. No guarantees about applications it might break, though.
/cah
--- Jeremy Porter, Freeside Communications, Inc. jerry@fc.net PO BOX 80315 Austin, Tx 78708 | 1-800-968-8750 | 512-458-9810 http://www.fc.net