Darren Spruell wrote:
> It's curious that the outside interface address on the cable modem
> is showing up for any reason on the internal network.
Right, this is what first puzzled me too.
> You might use tcpdump or similar on your internal network to
> determine what kind of traffic it relates to.
tcpdump -vv -x -l results attached below.
> Might help if you diagram it out, indicate IP addresses and subnets,
> and so on.
The setup right now:
WAN <-->
(WAN 24.aaa.bbb.ccc) SBG1000 cable-modem (LAN 192.168.0.1) <-->
(dc0: 192.168.0.10) OpenBSD ("rock") (fxp0: 192.168.1.11) <-->
other machines, phone, etc.
I hope the diagram above is clear. Basically, the WAN talks to the
SBG1000, which talks to the OpenBSD box, which talks to the inside
machines. The two IPs on each box show inward and outward addresses.
(I assume I shouldn't show my real IP or MAC addresses in public.)
The entire setup works; it just gives me the following message:
Feb 4 19:14:03 rock /bsd: arplookup: unable to enter address for
24.aaa.bbb.ccc
The SBG1000 does NAT and runs a DHCP server. I tried turning those
off so that the OpenBSD box would get its IP address directly from
the ISP's server, but that didn't fix the problem: I still got the
same arptables message, but with a different IP address.
I just ran tcpdump; here's the line at which I get the
error/warning/log message:
19:14:03.562039 arp who-has rock tell 24.aaa.bbb.ccc
[Note: 24.aaa.bbb.ccc is the cable-modem box's WAN address.]
0001 0800 0604 0001 000b 06bc 7b0e 1891
8674 0000 0000 0000 c0a8 000a 1102 1fdc
c0a8 6401 008a 00bb 0000 2046 4445
19:14:03.562118 arp reply rock is-at 00:11:22:33:44:55
[Note: 00:11:22:33:44:55 is the OpenBSD box's outward-facing NIC's MAC
address.]
0001 0800 0604 0002 0020 781f 00af c0a8
000a 000b 06bc 7b0e 1891 8674 1102 1fdc
c0a8 6401 008a 00bb 0000 2046 4445
Thanks for trying to help, guys.
J
