No ethernet connection to BBB when powered by 5V cable

[jaka.ko...@gmail.com]

Hello, I am a newbie trying to use two Beaglebone Black boards within the same lan network, and am having problems. Connecting them to PC with usb cable works fine, and I can connect to beaglebone.local fine with putty, and access built-in IDEs through web browser on windows.

The problems arise when I try to turn them on while powered by 5V cable, without usb. The Ethernet cable to my network is plugged before boot, and lights turn on as expected. But it appears the board does not broadcast into the network, and cannot be connected to with ssh. I tried setting up a static ip address when it was connected through usb, but it doesn't seem to help, putty connection timeouts on direct IP connection, and cannot find beaglebone.local hosts in the network. The weirdest thing is that the ethernet connection worked fine a few weeks ago, this problem started only recently.

I am booting the boards from an sd card with debian-9.9-iot image. What could be the cause of this? Is there a solution that isn't updating the image? Are the usb server and ethernet server on BBB different systems?

[Chris Green]

jaka.ko...@gmail.com wrote:
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>
> Hello, I am a newbie trying to use two Beaglebone Black boards within the
> same lan network, and am having problems. Connecting them to PC with usb

> cable works fine, and I can connect to *beaglebone.local* fine with putty,

> and access built-in IDEs through web browser on windows.
>
> The problems arise when I try to turn them on while powered by 5V cable,
> without usb. The Ethernet cable to my network is plugged before boot, and
> lights turn on as expected. But it appears the board does not broadcast
> into the network, and cannot be connected to with ssh. I tried setting up a static
> ip address

> <https://www.ofitselfso.com/Beagle/NetworkingSetupConnectingTheBeagleboneBlack.php>

> when it was connected through usb, but it doesn't seem to help, putty

> connection timeouts on direct IP connection, and cannot find*
> beaglebone.local* hosts in the network. The weirdest thing is that the

> ethernet connection worked fine a few weeks ago, this problem started only
> recently.
>
> I am booting the boards from an sd card with debian-9.9-iot image. What
> could be the cause of this? Is there a solution that isn't updating the
> image? Are the usb server and ethernet server on BBB different systems?
>

Is there a DHCP server on the LAN you are connecting these BBBs to?
If it is a router with web configuration you should be able to see
what IP address it has assigned to the BBBs.

Alternatively if you have a Linux/Unix system of some sort on the LAN
then install arp-scan and run "arp-scan -l" and it will show all IP
addresses on the LAN. It should then be fairly easy to work out the
addresses of the BBBs.

--
Chris Green
·

[jaka.ko...@gmail.com]

I figured something out - the problem was not in the boards, but in the network itself. The switch I connected the boards to was broken. Now I can get the BBBs to connect to internet and ping eachother. Thank you for help.