Simone72
Posts: 4
Joined: Fri Feb 19, 2016 1:41 pm

Ethernet port blinking even without cable plugged in

Wed Oct 02, 2019 10:15 am

Hello everyone,
I have three raspberries 3 Model B V1.2 that behave the same way.
If you ping them no problem but if I try to ping other PCs nothing to do.
The strange thing is that even if I disconnect the Ethernet cable, the ports seem to remain active with the LEDs flashing.
Some idea?

Thanks in advance,
Simone

pcmanbob
Posts: 10973
Joined: Fri May 31, 2013 9:28 pm
Location: Mansfield UK

Re: Ethernet port blinking even without cable plugged in

Wed Oct 02, 2019 12:52 pm

The LED's on the network port if booted from cold you should see one or 2 quick flashes if there is no network cable plugged in , plugging in network cable then both LED's should light in one should flash to indicate network traffic, removing the cable should see both LED's go out.

anything other than that would suggest a problem with the port or the network software/drivers on the SD card.

Have you tried booting the pi's in question with a fresh copy of raspbian just to eliminate a software problem or corrupted SD card ?
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Simone72
Posts: 4
Joined: Fri Feb 19, 2016 1:41 pm

Re: Ethernet port blinking even without cable plugged in

Wed Oct 02, 2019 2:07 pm

Thanks for the reply, unfortunately the same SD that I try on other Raspberry does not give any problem.
Complicated....

pcmanbob
Posts: 10973
Joined: Fri May 31, 2013 9:28 pm
Location: Mansfield UK

Re: Ethernet port blinking even without cable plugged in

Thu Oct 03, 2019 8:40 am

Simone72 wrote:
Wed Oct 02, 2019 2:07 pm
Thanks for the reply, unfortunately the same SD that I try on other Raspberry does not give any problem.
Complicated....
I would still try a fresh install for testing , it only takes a few minutes to flash the lite version of raspbian , but it looks like you have some hardware failure or damage.
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