This page describes common problems that users of Debian on plug computers
have run into. If you have any problems with your plug computer, either
while trying to install Debian or when running Debian, please look through
this page carefully to see whether you can find a solution. If your
problem is not covered here, feel free to contact the debian-arm list for help. Always
include the full boot log as well as the output of
printenv from U-Boot.
Cannot connect to serial console
If you cannot connect to the serial console of your plug computer, make sure that your device is working correctly. It has been reported that the power supply for SheevaPlug devices can stop working after continued use, so this might be the reason why you cannot connect to the serial console.
If your device is working correctly but you get a "permission denied" error
when connecting to the serial console, make sure that your user is in the
dialout group. This is the group associated with the
No output after "Uncompressing Linux..."
You get no output after seeing this line:
Uncompressing Linux... done, booting the kernel.
If you've just upgraded from Debian 6.0 (squeeze) to Debian 7 (wheezy), your version of u-boot is too old. You need 2011.12-3 (or higher). Please upgrade u-boot and everything will work again. There's no need to re-install Debian!
Error "Bad Magic Number" when loading image
Some users report that they get the following error when booting:
## Booting image at 00400000 ... Bad Magic Number
In most cases, the problem is not with the image itself but with loading the image. Take a look at the whole boot log and you'll probably find an earlier error, typically related to loading the image (maybe you specified a wrong location for the boot image; maybe the TFTP server didn't respond; maybe U-Boot failed to load the image from your USB stick). Look for the first problem in your boot log and you'll probably be able to figure out the solution.
Error "** Unable to read "/uImage" from usb 0:1 **" when booting
If you receive the error message
Unable to read "/uImage" from usb 0:1
when booting the first time, it's likely that
0:1 is not the correct boot
0:1 refers to device
0 and partition
1 but it's possible
that your boot partition is on a different device or partition.
In order to find out the correct device, you can use
usb dev (for USB) or
ide dev (for SATA) to see all devices. (Unfortunately, it's not possible
to list devices and partitions for MMC/SD cards with the current version of
u-boot.) In the following example, there is a single USB device (device
Marvell>> usb dev USB device 0: Vendor: A-JET Prod.: USB 2.0 0812 Rev: 1.00 Type: Removable Hard Disk Capacity: 1970.0 MB = 1.9 GB (4034560 x 512)
You can now display all partitions for this device with the
ide part for SATA devices):
Marvell>> usb part 0 Partition Map for USB device 0 -- Partition Type: DOS Partition Start Sector Num Sectors Type 1 2048 317440 83 2 319488 3211264 83 3 3532798 499714 5 Extd 5 3532800 499712 82
There are two partitions with the ext2/ext3 filesystem (type 83) and one
extended partition for swap (type 82). The first partition (partition
is the boot partition.
In the example, the device is device
0 and the boot partition is
1. Therefore, the correct path is
0:1. However, in your
case it might be something else.
Output "T T T T" when loading via TFTP
Some users report that they get the following output when loading an image via TFTP:
T T T T
This means that the TFTP server doesn't respond. Ensure that you specified the right IP address of the TFTP server and location of the image.
Also note that resetting the U-Boot environment may cause the plug computer
to try to load an image via TFTP. If you unexpectedly see the
T T T
messages, check your U-Boot configuration with
printenv to ensure it's
loading the image from the right location.
Boot fails with LVM on USB drive
If you have installed Debian on a USB drive and put the root device on a
LVM volume it's possible that the system won't boot because Debian tries to
access the LVM volume before the USB drive is recognized. To avoid this
problem, pass a
rootdelay parameter to the kernel. For example, issue
the following commands in U-Boot to give the USB drive 10 seconds to
bootargs_console console=ttyS0,115200 rootdelay=10
Loading image from a USB stick with FAT fails
U-Boot may have problems loading an image from a FAT32 filesystem whereas FAT works. I believe you can make a FAT filesystem under Linux with the following command:
mkfs.vfat -F 16
Formatting the disk is stuck at 33%
Formatting the disk may take a long time, especially if you have a large disk. Unfortunately, the progress bar is not updated while the disk is being formatted so you may think that it is stuck (at 33%). If this happens, just be patient. The installer is in fact formatting your disk.
eSATA disk not found on eSATA SheevaPlug
If your eSATA disk is not recognized on your eSATA SheevaPlug when booting Debian or the Debian installer, it's probably because you didn't use the correct kernel image. Make sure to use the kernel image for SheevaPlug with eSATA for the installation.