Re: Different behavior of ping'ing INADDR_BROADCAST?

Hi,

When FBSD is pinging 0xffffffff it does not use the Ethernet broadcasts,
when the link-level destination MAC is set to 0xffffffffffff, using some
'known MAC' instead. For the network broadcast address -- it does use
link-level broadcasts.

This seems to be the same problem as kern/99558: "FreeBSD 6.1 can't send
packets to INADDR_BROADCAST".

Maybe andre has some thoughts on how to fix this issue? (I'm CC'ing him.)

For me the 'known MAC' is that of our border router that serves as
the default destination. And my box doing the ARP request for the
precisely the IP of the router before pinging 255.255.255.255. You can
try to empty your ARP table and then ping 255.255.255.255 watching
for the ARP requests and the link-level header of the ICMP packets.

OK, I've found that in order to ping undirected broadcast address
one should add some functionality to the 'ping' utility.

It seems to me from the PR above, that before patching `ping', ip_output.c
should receive some sort of fix in handling INADDR_BROADCAST.

--
Tadaaki Nagao <nagao@xxxxxxxxx>
Applied Research and Development Department, Internet Initiative Japan Inc.
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