Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!uwmcsd1!ig!agate!ucbvax!NSIPO.NASA.GOV!medin From: medin@NSIPO.NASA.GOV ("Milo S. Medin", NASA ARC NSI Project Office) Newsgroups: comp.protocols.tcp-ip Subject: Re: ICMP's & IP src addrs Message-ID: <8809170420.AA00238@cincsac.arc.nasa.gov> Date: 17 Sep 88 04:20:02 GMT References: <303@wjh12.harvard.edu> Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 29 And I am sure that someones bridge will then decide that they know where "the broadcast address" lives and stop forwarding it. I have seen this (anti-social) behavior in DEC Lanbridges and it does not bode well for the network until someone resets the beast. Takes a while to find if you aren't looking for it. -- Gerald Lotto - Harvard Chemistry Dept. UUCP: {seismo,harpo,ihnp4,linus,allegra,ut-sally}!harvard!lotto ARPA: lotto@harvard.harvard.edu Actually, the Lanbridge, as all other bridges, looks at the source and destination addresses in the ethernet frame, NOT in the IP header. So this particular bug only is triggered by an ethernet frame with a source address of FFFFFFFFFFFF. The Sun's do have an annoying bug when turning around broadcast pings, but they do send them with the proper ethernet frame addresses. I have seen Kinetics Appletalk 'gateways' fail in such a way as to send ethernet frames with broadcast source addresses, and this does cause problems on a Rev. E LANBridge. DEC is working a fix though, and at least with LANBridges you can use RBMS to reset them remotely.... Thanks, Milo