rx_crc_errors from ethtool

Sanford Stein · 08-22-2008, 09:25 AM

I run 'ethtool -S' every morning and this morning I got 1500+ rx_crc_errors. This is the first time that this parameter has been non-zero.

Question 1: Is this a cumulative result? If so, starting when?
Question 2: What exactly is a rx_crc_error? Is my NIC card going bad?

Thanks,
Sanford Stein
CyberTools Inc.

Mr. C. · 08-23-2008, 05:56 PM

Ethtool stats are from the time the driver was instantiated (eg. loaded and inited).

RX means receive. CRC is cyclic redundancy check, a mathematical calculation that is used to identify errors in a packet.

This may indicate a hardware problem such as a cable problem, fault switch port, or other. Start first by replacing the cable.

Sanford Stein · 08-25-2008, 03:43 PM

Followup question for Mr. C or whoever else is listening:

If I am getting tx_error_bytes when running ethtool on one server in a communications link, and rx_crc_errors when running ethtool on the other, which NIC card is the most likely culprit? (We tried switching cables and the errors are still coming.)

Thanks,
SS

Mr. C. · 08-25-2008, 06:15 PM

Not sure. Can you describe how each device is connected to the other devices?

Sanford Stein · 08-26-2008, 10:41 AM

Mr C:

Thanks again for your quick response.

We had a third server in-house, so we tested the communication between servers 1 and 3, and then between 2 and 3, and this identified the NIC card on system 2 as the culprit and we will get a replacement from Dell.

SS

Mr. C. · 08-26-2008, 10:47 AM

Nice work isolating the hardware problem.

kamalsivadas · 04-08-2009, 11:49 PM

[QUOTE=Sanford Stein;3256013]I run 'ethtool -S' every morning and this morning I got 1500+ rx_crc_errors. This is the first time that this parameter has been non-zero.

Question 1: Is this a cumulative result? If so, starting when?
Question 2: What exactly is a rx_crc_error? Is my NIC card going bad?

Can you tell which driver you used to get 'ethtool -S' result??
The result is completely depends on driver!!.If you know any of the driver which supports all options of ethtool mention that also???