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prince_kenshi
04-21-2001, 06:06 AM
I just set up a FreeBSD machine on my network tonight. I thought the network wasn't working at all, but after trying it again with more patience, I found out it's just acting funny. When I ping my gateway, it sits there for a few seconds. Then it pops up with several responses simultaneously with descending times. Sometimes these times are around 5000 ms, sometimes more like 100000ms. (It seriously took about 100 seconds.) When I tracerouted Yahoo, it made it the full path but took 1998 ms to reach the gateway which I'm on now and it's about 10 feet away. On the bright side Yahoo was only a millesecond greater. A tcpdump showed nothing. When I traceroute from the gateway (Linux) to BSD, I get similar results. But the gateway and Windows 98 machine have no problem talking to each other. Since a Windows 2000 machine had had trouble with the same cable, I tried switching it with the one in mine but nothing changed. I did remove the motherboard from the box because of some grounding problems, but if it was causing electromagnetic interference, wouldn't it affect the whole network? I tried to make the ethernet cable run straight back from the computer to cause as little interference as possible. By the way, the hub is only a few feet away beside the monitor so it can't be something causing interference in the room unless it's the motherboard. Do you think it's interference? Is there some way I could test for that besides expensive equipment? Is there anything else to look at? Thanks for any help.

prince_kenshi
04-21-2001, 02:18 PM
I tested out the interference theory. I plugged the cable back into the Win 2K machine and pinged the gateway with all times >10ms. Then, with it still plugged into the same machine, wrapped the cable around the exposed BSD machine and pinged again. The times were still >10ms so it can't be interference.

prince_kenshi
04-21-2001, 03:21 PM
Another update: I installed tcpdump on the Linux machine to see what was going on from its point of view. While it was running, I pinged from the BSD box to the Windows box. Tcpdump showed an echo request every second and an echo reply less than 2 ms afterwards every time. But it doesn't show up on the BSD screen. The only time it does is when tcpdump shows these two lines:

14:14:14.404109 arp who-has kiran tell kenshi
14:14:14.404494 arp reply kiran is-at 0:50:ba:e2:a1:19

Kiran is the Windows machine and kenshi is the Linux machine. What are these arp packets for? Could this have something to do with how routing is set up?