How to remove a damaged Wired Connection

[Ralf Mardorf]

On Sun, 4 Sep 2016 09:45:02 +0100, Colin Law wrote:
>On 4 September 2016 at 09:34, Ralf Mardorf <silver.bullet at zoho.com>
>wrote:
>> On Sun, 4 Sep 2016 08:29:07 +0100, Colin Law wrote:  
>>>If the above is correct then it seems to me, as I previously
>>>suggested, that there is a problem with the router and nothing wrong
>>>with the PC at all.  
>>
>> Hi Colin,
>>
>> I disagree insofar as the OP does use Ubuntu 16.04 and by default
>> 16.04 doesn't use kernel device names anymore. What makes you thing
>> that the OP didn't screw up something by the customization? The
>> chain of evidence could suffer from fortuitousness.  
>
>If a machine is upgraded to 16.04 (rather than fresh install) then I
>believe that it stays with the ethn device names (at least that is my
>experience).

It sounds reasonable to stay compatible with already existing
configurations, but systemd could be tricky and might require tweaks to
work nicely with old configs, too.

>Also the fact remains that if all works well when the router is in a
>known good state but problems start when the router is in a known (but
>unknown) strange state then suspicion must surely fall primarily on
>the router. It appears to me that there is no evidence that there is
>anything wrong at the PC.

My doubts are based on the OP claims. Sometimes it is impossible to
power down the router. Did the OP really ensure that the router was
powered down? And again, regarding systemd and kernel name devices,
it's imaginable that there could happen race conditions. I don't know
when and why, I only want to point out that systemd might have an
issue. Anyway, the OP mentioned two buttons, the manual mentions three
buttons. What happens if the OP pushes the reset button, if it is
impossible to turn the router off by the power button?

The OP asks several times about disabling the eth0 device, but doesn't
follow already given advices, such as checking firmware upgrades.

Why doesn't the OP simply disable eth0?

IOW I more likely would have tendencies to agree with your reasoning, if
it would be your or my device, but I'm not sure that everything
happened exactly as described by the OP.

Regards,
Ralf