Well naturally I shot myself in the foot by not giving everyone the full info. Careful readers will notice that I'm executing a Xen kernel, and indeed if I was in a Xen domU (guest VM) then my problem would have been truly mystifying. However, I am executing in dom0 (the VMM domain), which has a somewhat more complicated view of system networking. Specifically, there are bridges and virtual interfaces. I think my problem is arising because bridges operate at the MAC level and not the IP level. So right now I'm looking into ebtables to fix my problem. I'll report back if/when I figure it out entirely. Steve Brueckner, ATC-NY
