[tulip-bug] Linksys PCMPC200 requires PROMISC mode to recieve? [.92]
Scott A Crosby
crosby@qwes.math.cmu.edu
Mon, 25 Sep 2000 02:02:41 -0400 (EDT)
Hello. I have a `Linksys EtherFast Cardbus 10/100' PCMCIA card. (Model
number: PCMPC200) that was bought a week ago. Although the most recent
version of the driver [.92] works without problems, for some reason, I
need to keep the card in promiscious mode
If I don't....
For example: From the perspective of another host on the network. (Here,
10.2.3.5, the laptop, is trying to ping the base station: dragonlight.
21:44:33.855332 arp who-has dragonlight tell 10.2.3.5
21:44:33.855374 arp reply dragonlight is-at 0:50:da:6c:c9:93
21:44:34.855302 arp who-has dragonlight tell 10.2.3.5
21:44:34.855344 arp reply dragonlight is-at 0:50:da:6c:c9:93
It is getting responses, but it's not using them for some reason.
Here, I am pinging to the laptop:
21:46:57.429317 arp who-has 10.2.3.5 tell dragonlight
21:46:57.429457 dragonlight > 10.2.3.5: icmp: echo request
21:46:58.429426 arp who-has 10.2.3.5 tell dragonlight
21:46:58.429515 dragonlight > 10.2.3.5: icmp: echo request
dragonlight is using it's ARP cache to try satisfy the requests. It's also
trying to verify that it's ARP entry is accurate with the additional ARP
requests.
The symptoms seem as if the ethernet card isn't sending packet's to the
kernel unless PROMISC mode is set. When PROMISC is set, all this
automagically goes away.
I'm starting the network card with:
ifconfig eth0 10.2.3.5 netmask 255.255.0.0 broadcast 10.2.255.255 promisc arp up
route add -net 10.2.0.0 netmask 255.255.0.0 eth0
Which should have been all I needed. If I make it '-promisc', I get the
above failures.
Here's 'ifconfig' for when in PROMISC mode and it works.
eth0 Link encap:Ethernet HWaddr xx:xx:xx:xx:xx:xx
inet addr:10.2.3.5 Bcast:10.2.255.255 Mask:255.255.0.0
UP BROADCAST RUNNING PROMISC MTU:1500 Metric:1
RX packets:667 errors:0 dropped:0 overruns:0 frame:0
TX packets:631 errors:6 dropped:0 overruns:6 carrier:1
collisions:0 txqueuelen:100
Interrupt:3 Base address:0xe000
hypercube:/usr/src/linux# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.2.0.0 * 255.255.0.0 U 0 0 0 eth0
10.2.0.0 * 255.255.0.0 U 0 0 0 eth0
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