Re: Lan performance issues

From: Matt Garman (fake_at_not-real.bogus)
Date: 12/06/03

Date: Sat, 06 Dec 2003 20:03:56 GMT

On Sat, 6 Dec 2003 00:35:52 +0100, Michael Heiming
<> wrote:
> Looks not that bad, even if you usually see bad cable from errors
> above, I'd try out another cable, not some self-made, just to be sure.

I verified that all my cables are indeed Cat5 (actually, they are "CAT5e
UTP"). Note that my roommate has a Windows 2k box also attached to the
switch. Transfers from the server to his computer also cap around 230

> The BSD box isn't running some kind of traffic shaper? In addition I'd
> use a cross-over cable, to exclude the switch from testing.

Nope, the BSD box is not running any kind of traffic shaper. I verified
this by transferring a file between my computer (Linux) and my
roommate's computer (Win2k). The speed was actually halved! (I got
about 120 KB/s.)

I also bought a crossover cable, and ran it between the Linux and
OpenBSD boxes. The transfer speeds did not improve.

> Perhaps forcing the NIC to 10 Mb, like Peter T. Breuer suggested, to
> see if your cable work better at this speed, would be another good
> idea. You can set this with mii-tool/mii-diag while running.

I set the Linux box to 10baseT, and my transfer speeds were actually
*reduced* by about 1/3 (went down to around 80 KB/s).

Finally, since the OpenBSD box has two NICs (a Linksys and a
Realtek-based card), I swapped their roles. Originally, the Linksys was
for the LAN, and the Realtek was for the DSL. Now the Linksys is
connected to the DSL and the Realtek is connected to the LAN. No
improvement in performance. :(

I'm starting to think I have multiple points of failure.

Any more thoughts? Looks like I actually need to start physically
swapping NICs.

Thanks for all the help guys!

Matt Garman
email at:

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