I did receive the very same answer. It's good to see that some attention is being drawn to this problem and hopefully they will find a fix soon.

I will not believe that the problem with "not being able to connect 2 x Gigabit ethernet" is related to the power supply overheating, or did they say it has something else to do with the power supply? The reasoning is that while on the u-boot prompt just sitting there and doing nothing doesn't make my plug reboot. Working in Linux does.

Therefor I really believe it is driver related.

Right, well it fixes things for the short term, it is ofcourse not a long term solution

So, how to fix the plug so that it runs 2xGigabit without rebooting ...

Hi Ashcrow,

You are so right. The only question now remains ... is this a hardware issue (and should the unit be RMA'd), or is it fixable in u-boot or kernel (so driver related).

My guess is its driver related. (I really hope ... )

The reasoning why I think it's driver related is that if you Google on the PHY in these plugs (88e1121) you can find some kernel fixes way way back (also see my post earlier). My guess is that the 88e1121 on the Guruplug board shares its bus with both ports, making interrupts flying in a tricky business. Hence the rebooting when you use both ports.

These are just my 2 cents, I'm not a kernel hacker nor anyway specialized in this stuff ...
Makes me wonder, are people of Marvell reading these forums? If so ... please take a look at the drivers and see if these are correctly working...

What now happens when you connect a cable to eth1? And which cable do you use? The one supplied or another one?


No, that would be silly


I'm going to build a kernel which does not compile the WiFi at all ... don't really need it.

I think it's good to know the following from all the users with problems:

 - Guruplug Server or Server Plus?
 - Is your plug on 110v or 220v+
 - Do you have ethernet connected? and if, only ETH0 or 1 or both?

My latest guess is that the rebooting issues are not power related, nor heat related.
I think that it has something to do with the ethernet drivers (in both u-boot and the kernel, or one of the two).

See a patch submission to u-boot back in December 2008, this is about the Marvell 88E1121 (the PHY in the Guruplug Server Plus);
http://www.mail-archive.com/u-boot@lists.denx.de/msg05529.html

I know my plug is stable when there is no ethernet connected to it. The moment I connect ethernet to it, it becomes unreliable. Unfortunately I do not have the required knowledge to "debug" this deeper, but I think I'm on to something.

So those who have issues with their Guruplug, let us know what and how you have stuff connected, and on what voltage you are running your plug. (although I do not think voltage has anything to do with it).   

I really do wonder what the problem is with the plug, at this moment its a bit unstable to really use.
Is it a hardware issue? Was is pushed out too early? Is the problem only in Europe (with our 230-240v)?

What I found out;

 - It seems not to be kernel nor u-boot related
 - If I put a cable in eth1, it keeps on working most of the time
 - If I put a cable in eth0, it doesn't keep working all the time
 - If I put a cable in both eth0 and eth1, the plug reboots and keeps in that loop until it cold boots

What does seem to make a different is what kind of cable is used. Or better, is it a self made cable or a premade...

Honestly I cannot get a firm grip on the "issue" but I would like to see what others tried to resolve it ... if its already resolved.