High RX errors on Intel 82547 chipset

Intel 82547 ( Gigabit Ethernet ) on Gigabyte GA-8IPE1000 Pro2

Running RedHat 7.2 with latest RPMs.
Pentium4 with hyperthreading and using 2.4.20 i686 RedHat SMP kernel

Added the following to /etc/modules.conf to force it to 100Mb
full-duplex ( since the hub and switched would not be able to handle
Gigabit ethernet yet ):

alias eth0 e1000
options e1000 Speed=100 Duplex=2


Got everything installed and working.
However, I just realised today the high number of RX errors reported by
ifconfig. No wonder the network connection seems "slow".

$ /sbin/ifconfig
eth0 Link encap:Ethernet HWaddr 00:0D:61:10:05:4A
inet addr:192.168.0.50 Bcast:192.168.0.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:10609 errors:2225 dropped:0 overruns:0 frame:2225
TX packets:5791 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:6526058 (6.2 Mb) TX bytes:573509 (560.0 Kb)
Interrupt:18 Base address:0xa000 Memory:f6000000-f6020000



I tried:
1) The built-in e1000 driver from RedHat's 2.4.20-SMP-i686 kernel
2) The latest driver from Intel, with specific support for the Intel
82547 chipset

Both are showing a high number of RX errors.

Help!

noone wrote:
> Intel 82547 ( Gigabit Ethernet ) on Gigabyte GA-8IPE1000 Pro2
>
> Running RedHat 7.2 with latest RPMs.
> Pentium4 with hyperthreading and using 2.4.20 i686 RedHat SMP kernel
>
> Added the following to /etc/modules.conf to force it to 100Mb
> full-duplex ( since the hub and switched would not be able to handle
> Gigabit ethernet yet ):
>
> alias eth0 e1000
> options e1000 Speed=100 Duplex=2
>
>

Got it ... I commented out the line:

options e1000 Speed=100 Duplex=2

No more RX errors, and still at 100Mbps / full-duplex.
Why? Don't know

noone wrote:

< snip >

> Got it ... I commented out the line:
>
> options e1000 Speed=100 Duplex=2
>
> No more RX errors, and still at 100Mbps / full-duplex.
> Why? Don't know

Because (1) you are not really running full duplex, you just think you are,
and (2) your hub doesn't actually support full-duplex. It is rarely useful
to try to second-guess the autoconfiguration of NICs and hubs.

--
Paul Lutus
http://www.arachnoid.com

Paul Lutus wrote:
> noone wrote:
>
> < snip >
>
>>Got it ... I commented out the line:
>>
>>options e1000 Speed=100 Duplex=2
>>
>>No more RX errors, and still at 100Mbps / full-duplex.
>>Why? Don't know
>
>
> Because (1) you are not really running full duplex, you just think you are,

You're telling me that the log is lying:

root@mig-linux log]# grep e1000 messages.4
Oct 7 17:53:59 localhost kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 7 18:03:38 localhost kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 7 18:50:16 localhost kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 11:13:13 localhost kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 12:05:37 localhost kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 12:11:13 mig-linux kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 12:16:53 mig-linux kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 13:03:06 mig-linux kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 13:05:48 mig-linux kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 13:22:29 mig-linux kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 13:22:57 mig-linux kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 13:50:11 mig-linux kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 17:26:08 mig-linux kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 18:04:00 mig-linux kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 18:07:24 mig-linux kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 19:06:04 mig-linux kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 19:13:05 mig-linux kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 19:18:00 mig-linux kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex
Oct 8 20:28:18 mig-linux kernel: e1000: eth0 NIC Link is Up 100 Mbps
Full Duplex


> and (2) your hub doesn't actually support full-duplex. It is rarely useful
> to try to second-guess the autoconfiguration of NICs and hubs.
>

Except that the hub does support full-dupliex. All of the NICs connected
to the same hub are at full duplex ( including the those NICs in windose )

noone wrote:
> Except that the hub does support full-dupliex. All of the NICs connected
> to the same hub are at full duplex ( including the those NICs in windose )

Maybe forcing speed and duplex like that didn't force the correct
flow control setting too...

Mike


--
Mike Jagdis Web: http://www.eris-associates.co.uk
Eris Associates Limited Tel: +44 7780 608 368
Reading, England Fax: +44 118 926 6974

Mike Jagdis wrote:
> noone wrote:
>
>> Except that the hub does support full-dupliex. All of the NICs
>> connected to the same hub are at full duplex ( including the those
>> NICs in windose )
>
>
> Maybe forcing speed and duplex like that didn't force the correct
> flow control setting too...

In fact the e1000 driver says:

/* Turn off Flow control if we are forcing speed and duplex. */
hw->fc = e1000_fc_none;

so if one end just can't keep up...

Mike

--
Mike Jagdis Web: http://www.eris-associates.co.uk
Eris Associates Limited Tel: +44 7780 608 368
Reading, England Fax: +44 118 926 6974