A20 doesn't boot fully with Ethernet cable connected

[ghofer]

I am able to boot debian on the A20 board successfully until I plug in an Ethernet cable.  After I power down and back up, the unit won't boot completely.  I just get a black screen with a black X mouse cursor with white borders.  I can ping the A-20 unit from my PC connect to the same router so the unit appears to be alive.  Any idea why this is?  Thanks.

[soenke]

Login using SSH and check the logs.

[ghofer]

There are a lot of log files in /var/log.  Which one should I be looking at and what messages should I be looking for?  I'm new to linux so not sure where to go to find the log info quickly.  We thought that maybe the power supply was not sufficient but the current one is 9W and it still won't boot with the Ethernet cable connected.

[soenke]

Good thing with linux is, that you can find a solution in the internet for almost any problem or error message.

Have a look into /var/log/syslog and /var/log/Xorg* and check for possible errors. In Xorg (EE) means error.

[MBR]

What device is connected to the other end of the cable? A router/switch, or an PC/laptorp/whatever? How long is the ethernet cable?

And some wild speculations stuff: is the A20 powered from the same branch of electrical wiring (i.e. with the same circuit breaker)? Although the ethernet has transformer coupling (the "black thingie" near the RJ45 connector or MAGJACK with build-in transformers) that should be resistant to the ground offset, in some pathological cases even that may be insufficient - the device will hang or behave strangely as long as the cable is plugged in.

[soenke]

As he can log in with SSH i dont think it is an ethernet issue. I think more of some service that tries to start when there is a network connection and blocks Xorg from starting correctly. Maybe waiting some minutes for a timeout could help

[saarijoki]

Even though it's clearly not an issue directly with the ethernet connection, I'd check the /etc/network (especially the if-pre-up.d and if-up.d) and the Xorg startup scripts to see if there's something funny there. Also, disable all the candy in the desktop and some desktop-related applications and/or plugins you might have installed prior to failure.