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-   -   Lots of RX errors on internal eth (

pembo13 08-15-2004 07:40 AM

Lots of RX errors on internal eth

I've been noticing many many errors on my server when receiving from my client. Infact I even started a threat here
because I thougth my slow ftp transfers were due to the ftp daemon and not my network hardware.

I've since changed the wire from client to switch with no effect (replaced it with a brand new pre-fab). I then changed the wire from the server to the switch with a much shorter wire, but not brand new, and that gave a dramatic increase in uploads to the server from an average of 20 KB/s to over 3MB/s.

However there are still alot of RX errors on the receivng eth, even during normal masquerading. I would really like to solve these errors. My next step is to replace teh older wire with a brand new pre-fab too.

But what else could be casuing these errors? Mine is a small setup so it accept all traffic on the internal eth. Could my Cat5 passing very close to a 220V-110V transformer cause such errors? That's the only thing I can think of.


arno 08-15-2004 10:12 AM

Things that can cause the problem:
1) Noise of electronic application
a) transformer
b) cell phone
c) TL-light (transformer)
d) (high)-power cable
as a rule there impact is limited due to the distant, keep about a foot between cable and object

2) bad cable or connector

3) "bad" nic
In most nic's you can change the setting with the help of software which came with the nic.
Sometimes it's helpful to set the nic to a certain fixed speed instead of auto sensing
and there are situation's where half duplex helps

pembo13 08-15-2004 11:38 AM

Well that proves it then. I have the cat5 passing within 2 inches of a transformer...I'm going to have to get new,shorter cables adn relocate the switch. Luckily I can do the cabling myself, but I don't have any spare cable, so till Monday for me.

Thank you

pembo13 08-17-2004 10:13 AM

Well I've changed the wires, made fresh ones up with my crimp. I made them the shortest possible length, I pushed teh transformer about 12 inches away. My transfers have jumped up to about 10MB/s.

But I'm STILL getting RX errors on the receiving end. How can I further troubleshoot this?

arno 08-17-2004 02:48 PM

Is it 10 MB or 10Mb, 10MB is about the maximum a 100 Mb switch can transport.
When you use a switch it could even be one of the other computers connected to the switch who messes up the traffic.
To check this you could use a cross cable to connect your server to your computer and do the test again.

pembo13 08-17-2004 06:30 PM

Ah, interesting. An here I was thinking that 100MB/s was the maximum for a 100Mb switch.....I guess I need to go over my basic computer data types.

However, I've conducted my tests with only the server, the switch and the one client on. Should a test with a cross over cable stil be neccessary?

Thank you.

arno 08-18-2004 08:03 AM

With that test you pin point which nic or device is creating the problem.
At one time i was faced with a network problem ( a switch giving problems) which was cause by a cable, even though the computer was switched off it generated a lot of error's.
Modern computers have (remote)power-on capability with on board nic that's possible because the nic's always powered only if you pull the power cord your computer is switched off

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