Re: [PLUG] open source copper ethernet tester

[Chad Waters via plug <plug@lists.phillylinux.org>]

So it actually looks like ethtool can do it *if you can find an nic that supports it*.  

ethtool --cable-test eth0     
AND
ethtool --cable-test-tdr eth0 


I dont have one on hand. If anyone know a  USB to GigE dongle that can do this let me know. Now I just what one because I miss having a Fluke from my networking days. 

Anyways. I re-punched the run and got it working. ¯\_(ツ)_/¯

Thanks,
Chad

On Sunday, March 15th, 2026 at 9:53 AM, Chad Waters via plug <plug@lists.phillylinux.org> wrote:with kernel modules to support it.


> 
> I redid some cat6 in my house, now I have 1 run that I cant get GigEthernet on. It negotiates down to FastEthernet (100M). I cant figure out the issue. Does anyone know of a opensource layer 1 tester?
> 
> Something that would tell me what a $3k Fluke would tell me: ie "there's a fault 30 feet down wire 1"
> https://www.fluke.com/en-us/products/network-cable-testers/copper
> 
> I have a retail grade tester, but that only gives you connectivity mapping on the wires.
> 
> Thanks
> -Chad
> 
> 
> 
> 
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