(revised) 4.*9*-stable & Linksys WRT54G won't talk w/each other

[Kenneth W Cochran]

>Date: Fri, 9 Jan 2004 12:56:20 -0500 (EST)
>From: Anthony Volodkin <anthonyv at brainlink.com>
>To: Kenneth W Cochran <kwc at theworld.com>
>cc: freebsd-net at freebsd.org, <freebsd-questions at freebsd.org>
>Subject: Re: (revised) 4.0-stable & Linksys WRT54G won't talk w/each other
>
>Hey,
>
>Apparently the WRT54G is having some arp issues.  I'd check the following:
>
>- install latest firmware

Have avoided that so far b/c I wanted to be able to do that from
FreeBSD, e.g. with tftp...
But I might just go ahead & do that via Windows.  {shrug}

>- install Ethereal on the windows machine and watch the traffic exchange
>when you would ping/access the WRT54G.  It is important that this is done
>right after boot so that the Windows machine does not have the MAC of
>WRT54G cached.  It'd be interesting to compare the arp requests from the
>FreeBSD machine to ones from the Win2k one, if that seems at all
>different.

Have thought about that too, especially since trying to
tcpdump dc2 with the Windows box connected to the Linksys
resulted in nothing (the "inside" part of the Linksys is
a switch).

>- Finally, I assumed that the cable that you are using to connect the
>freebsd box to WRT54G is just as good as the one you use with the Windows
>machine.

Yup, cables & interfaces are all good; 1st thing I checked.

>-Anthony

-kc

>On Fri, 9 Jan 2004, Kenneth W Cochran wrote:
>
>> Hello:
>>
>> I'm having problems getting a FreeBSD machine and a Linksys
>> WRT54G talking with each other.
>>
>> Interfaces:
>> dc0 - "public" to outside Internet
>> dc1 - internal 192.168.0.1/24, connects to a hub
>> dc2 - internal 192.168.1.100/24, connects to a switched LAN port on the router
>> dc3 - currently unused
>>
>> OS: FreeBSD 4.9-STABLE as of 10 December 2003
>> firewall: ipfw2
>> Running natd between dc0 & dc1 (& that works fine)
>>
>> dc0 gets its IP address, etc., via DHCP/dhclient.
>> dc1 is configured statically & machines connected on that subnet work fine.
>> dc2 should get its ip address, etc. from a Linksys WRT54G,
>>     but won't; syslog says "address in use," so I configured it "manually"
>>     with ifconfig, to 192.168.1.100/24.
>>
>> Problems/questions:
>>
>> dc2 has a Linksys WRT54G on it, & thus far, that box refuses
>> to talk (not even icmp) with the fbsd machine, even if I set
>> its ip-address & that of dc2 manually.  (The Linksys
>> defaults to running a dhcp server & its factory-supplied
>> ip-address is 192.168.1.1 & it "tries" to setup the first
>> interface talking to it to be 192.168.1.100).  The router
>> works fine when connecting another machine (running Windows
>> 2000) to it.
>>
>> As examples:
>> $ ping -c3 192.168.0.2  ## this is a Windows2000 box on the dc1 network
>> PING 192.168.0.2 (192.168.0.2): 56 data bytes
>> 64 bytes from 192.168.0.2: icmp_seq=0 ttl=128 time=0.391 ms
>> 64 bytes from 192.168.0.2: icmp_seq=1 ttl=128 time=0.177 ms
>> 64 bytes from 192.168.0.2: icmp_seq=2 ttl=128 time=0.232 ms
>>
>> --- 192.168.0.2 ping statistics ---
>> 3 packets transmitted, 3 packets received, 0% packet loss
>> round-trip min/avg/max/stddev = 0.177/0.267/0.391/0.091 ms
>>
>> localhost# tcpdump -lni dc1  ## tcpdump while running the above ping
>> tcpdump: listening on dc1
>> 10:15:39.882162 arp who-has 192.168.0.2 tell 192.168.0.1
>> 10:15:39.882305 arp reply 192.168.0.2 is-at 0:90:27:84:42:f
>> 10:15:39.882318 192.168.0.1 > 192.168.0.2: icmp: echo request
>> 10:15:39.882492 192.168.0.2 > 192.168.0.1: icmp: echo reply
>> 10:15:40.883394 192.168.0.1 > 192.168.0.2: icmp: echo request
>> 10:15:40.883511 192.168.0.2 > 192.168.0.1: icmp: echo reply
>> 10:15:41.893417 192.168.0.1 > 192.168.0.2: icmp: echo request
>> 10:15:41.893584 192.168.0.2 > 192.168.0.1: icmp: echo reply
>>
>> $ ping -c3 192.168.1.1  ## ip address of the router on dc2
>> PING 192.168.1.1 (192.168.1.1): 56 data bytes
>>
>> --- 192.168.1.1 ping statistics ---
>> 3 packets transmitted, 0 packets received, 100% packet loss
>>
>> localhost# tcpdump -lni dc2  ## tcpdump while running the above ping
>> tcpdump: listening on dc2
>> 10:17:18.123385 arp who-has 192.168.1.1 tell 192.168.1.100
>> 10:17:19.124588 arp who-has 192.168.1.1 tell 192.168.1.100
>> 10:17:20.134583 arp who-has 192.168.1.1 tell 192.168.1.100
>>
>> Any ideas on getting this thing to work?  It seems to work
>> fine when connected to a Windows2000 machine.
>> Yes, I've tried other interfaces & cables, etc, so I'm
>> confident the hardware is fine. :)
>>
>> Idea(s) on further troubleshooting/fixing this?
>>
>> FAQs/documentation pointers are quite welcome. :)
>>
>> Thanks,
>>
>> -kc