ethernet transmit errors

In the last few months I've recently added an ethernet card and a wireless
ADSL router to my system for broadband use. It's been working flawlessly
for about 3 months, but recently I've noticed a few delays and timeouts
when trying to browse the web or even trying to connect to the router.

The light for the ethernet connection often goes out while the ADSL light
is consistently on so I don't think it's problems my ISP. Plus an ifconfig
shows lots of Tx errors:

eth0 Link encap:Ethernet HWaddr 00:00:E8:13:2C:43
inet addr:192.168.1.3 Bcast:192.168.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:2950 errors:0 dropped:0 overruns:0 frame:0
TX packets:2684 errors:32 dropped:0 overruns:0 carrier:32
collisions:0 txqueuelen:1000
RX bytes:1728374 (1.6 MiB) TX bytes:217821 (212.7 KiB)
Interrupt:10 Base address:0xac00

The above is only covers about 15mins. To me 32 errors in that time seems
quite a lot

My question is how can I work out whether this is a hardware or software
problem? If it's hardware how can I tell whether it's the router or my
ethernet card? I don't have any spares with which to swap out.

Also, the 'network statistics' of my router show no errors, does this mean
that the problem lies with the ethernet card rather than the router?
TIA

Router: Safecom GART2-4115/SWART2-54125
Ethernet card: Safecom SNIC-10100

lspci:
0000:00:0f.0 Ethernet controller: Linksys NC100 Network Everywhere Fast Ethernet 10/100 (rev 11)
dmesg:
[17179587.456000] eth0: ADMtek Comet rev 17 at 0001ac00, 00:00:E8:13:2C:43, IRQ 10.
[17179592.796000] eth0: Setting full-duplex based on MII#1 link partner capability of 41e1.

On Fri, 13 Oct 2006 20:21:35 +0100, Chris wrote:

> In the last few months I've recently added an ethernet card and a wireless
> ADSL router to my system for broadband use. It's been working flawlessly
> for about 3 months, but recently I've noticed a few delays and timeouts
> when trying to browse the web or even trying to connect to the router.
>
> The light for the ethernet connection often goes out while the ADSL light
> is consistently on so I don't think it's problems my ISP. Plus an ifconfig
> shows lots of Tx errors:
>
> eth0 Link encap:Ethernet HWaddr 00:00:E8:13:2C:43
> inet addr:192.168.1.3 Bcast:192.168.1.255 Mask:255.255.255.0
> UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
> RX packets:2950 errors:0 dropped:0 overruns:0 frame:0
> TX packets:2684 errors:32 dropped:0 overruns:0 carrier:32
> collisions:0 txqueuelen:1000
> RX bytes:1728374 (1.6 MiB) TX bytes:217821 (212.7 KiB)
> Interrupt:10 Base address:0xac00
>
> The above is only covers about 15mins. To me 32 errors in that time seems
> quite a lot
>
> My question is how can I work out whether this is a hardware or software
> problem? If it's hardware how can I tell whether it's the router or my
> ethernet card? I don't have any spares with which to swap out.
>
> Also, the 'network statistics' of my router show no errors, does this mean
> that the problem lies with the ethernet card rather than the router?
> TIA
>
> Router: Safecom GART2-4115/SWART2-54125
> Ethernet card: Safecom SNIC-10100
>
> lspci:
> 0000:00:0f.0 Ethernet controller: Linksys NC100 Network Everywhere Fast Ethernet 10/100 (rev 11)
> dmesg:
> [17179587.456000] eth0: ADMtek Comet rev 17 at 0001ac00, 00:00:E8:13:2C:43, IRQ 10.
> [17179592.796000] eth0: Setting full-duplex based on MII#1 link partner capability of 41e1.


check your cables, replace the older, 'thinner' ones with newer
cables, swap them to different ports if possible. Carrier errors are
usually noise / collisions on the cables.

jack


--
D.A.M. - Mothers Against Dyslexia

see http://www.jacksnodgrass.com for my contact info.

jack - Grapevine/Richardson

On Fri, 13 Oct 2006 19:32:43 +0000, Jack Snodgrass wrote:

> On Fri, 13 Oct 2006 20:21:35 +0100, Chris wrote:

[ snip Tx errors on eth0 ]

>
>
> check your cables, replace the older, 'thinner' ones with newer
> cables, swap them to different ports if possible. Carrier errors are
> usually noise / collisions on the cables.
>

Thanks Jack. I didn't think of the cable, doh! I'll borrow a cable from
work and see if that helps...

On Fri, 13 Oct 2006, in the Usenet newsgroup comp.os.linux.networking, in
article <(E-Mail Removed)>, Chris wrote:

>The light for the ethernet connection often goes out while the ADSL light
>is consistently on so I don't think it's problems my ISP. Plus an ifconfig
>shows lots of Tx errors:

>eth0 Link encap:Ethernet HWaddr 00:00:E8:13:2C:43

[compton ~]$ etherwhois 00:00:E8
00-00-E8 (hex) ACCTON TECHNOLOGY CORP.
0000E8 (base 16) ACCTON TECHNOLOGY CORP.
46750 FREMONT BLVD. #104
FREMONT CA 94538
UNITED STATES
[compton ~]$

> RX packets:2950 errors:0 dropped:0 overruns:0 frame:0
> TX packets:2684 errors:32 dropped:0 overruns:0 carrier:32
> collisions:0 txqueuelen:1000

A "carrier" error means that the signals coming out of the card are not
what the 'data' looked like. On the original coaxial network, this was
caused by a shorted cable or an open circuit. The driver is trying to
"shake" the wire, but the wire just isn't moving. In a twisted pair
environment, this _usually_ indicates a cable problem (bad cable, or
cable not securely plugged in), but _may_ indicate failing hardware.
A common check I use is to flog the crap out of the system by sending
large amounts of data to a nearby peer, and looking at the ifconfig
errors on both systems. Is one system reporting received errors
(specifically frame errors) which indicates an intermittent? If using
ping as a test, is it showing missing sequence numbers?

>The above is only covers about 15mins. To me 32 errors in that time seems
>quite a lot

32 Carrier, Dropped, or Frame errors would be a lot. The 'dropped' would
indicate a continuing problem involving failed retransmits. Overruns only
mean that the link is busy, and the computer is busier, and didn't have
time to unload the data from the NIC before more data arrived. Collisions
on a half duplex non-switched network are common.

>Also, the 'network statistics' of my router show no errors, does this mean
>that the problem lies with the ethernet card rather than the router?

Depends if it is showing Ethernet statistics rather that IP or TCP.

The fact that this worked for three months, then went South suggests that
either the plug got loose or the cable got damaged (pinched is fairly
common). If this is 100BaseT, this could also indicate low quality cables
(not twisted as tightly as spec) that got moved closer to something that is
interfering or is causing an impedance bump (a metal file cabinet setting
on the cable would not only crush it, but could cause electronic reflections
that would play havoc with the signals).

Old guy