[lug] ARP packets not seen?
David L. Anselmi
anselmi at anselmi.us
Sun Jul 19 11:39:06 MDT 2009
> I'm guessing that either I have a defective switch (Linksys 5-port
> 10/100 cheap-ass switch, so not outside the realm of possibility), or
> that something on the linux box is keeping those ARP replies from
> reaching the switch in the first place.
Swap out the port and cable (and NIC if you can) with known good ones.
If the kernel is generating ARP replies it shouldn't be blocking them.
Check that you have no firewalling on the Linux box.
Check your selinux settings. I don't think it has any relation to
networking but it's also been the culprit in other stupid "everything is
correct but it still doesn't work" problems.
> p.s. I also noticed that doing a manual configuration on the linux
> box, and then bringing the interface down then up, made a entry
> in the routing table for 169.254.0.0 ... no idea why, and I worry
> that it's somehow sending packets off into the weeds.
That's a zeroconf address. MS calls it APIPA. If you go through all
the effort of learning the zeroconf components and configuring them
across your network it might be a good thing. But otherwise you want it
turned off. At the moment it's a toss-up whether I'll learn IPv6 or
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