Check to see how many collisions you are getting on the network.

Also, for further diagnosis, it would be benificial to report if you are
running a kernel that you compiled or the generic, etc. You can also
specify the media parameters that will be supported with that driver by
defining the media type int the hostname.xxx file. (see "man hostname.if")

Keep in mind, that if you are seeing 300Kbps (not 300kbps) that you are
just about maxing out what a 10Mbit NIC can do on a non-switched network
(about 3.3 Megabits is common; depends). If collisions are high, then that
explains degredation in throughput. Ethernet uses a back-off algorithm to
retransmit to avoid more collisions. These things take time. If there are
only 2 hosts on the net though, this may not be the main issue, but can
still happen when they are not in full dup. Full duplex does not work on a
hub, only host to host, or host to switch.

If you want to see if collisions are the problem, a good way to bypass
this is to back-to-back the 2 puters with a crossover cable. Then you can
kick it up to full dup and see how things go.

Good luck man.

.aan

"Never snip the pair that transmits."

On Thu, 5 Apr 2001, Tom Van de Wiele wrote:

> Hi,
>
> Situation:
> client: PII266Mhz/98meg RAM running winnt4.0wks and debian2.2 with a 3C900
> (etherlink pci combo) 10Mbit ethernetcard
>
> server: P133Mhz/40meg RAM running openbsd 2.8 also with a 3C900
> (etherlink pci combo) 10Mbit ethernetcard
>
> The problem is: I can only get transferspeeds arround 300kb/sec max on
> my network. The NIC's are set in half-duplex mode now, where I get an
> average of 300kb/sec. If I put them in full-duplex mode (with the
> 3c90xcfg.exe program supplied by 3com) and put them in full-duplex in
> the OS, I can only get a maximum of 20kb/sec (?!). I tried to see if
> the problem was my 10Mbit hub, but I tried using a cross-link cable
> between the two, which gave the same results. All my cables are
> CAT-5. I've tested speeds using an upload and a download of a 3
> megabyte file with ftpd and httpd. I also tried a pingflood from the
> server to the client while looking at the datathroughput with "iptraf"
> on the client. The maximum is always 300 to 330 kb/sec...
>
> I thought 3com cards were well supported? I've posted this problem to
> this list a couple of times and asked this on many IRC
> channels, and didn't get any solutions to work with... I'm going to
> continue to ask and search for the answer till the end of the week.
> If all else fails, I'm going to switch operating systems and install
> freebsd or linux. You can be "secure by default" all you want, I
> want full network performance. I've been coping with this problem for
> about two months now and I've had it. And to be honest, I'm a little
> dissapointed.
>
> Kind regards
>
> -- Tom
>
>
>
> -------------------
> toshtorn.be
>
> pubkey on demand
> fingerprint:
> 49D5 E342 26EF 984E 5FD6 38B6 C457 4FFD 731E 63E3

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