TroubleShooting

My program does not start

If your program does not start

• make sure you have execute priviledges for it using the command

ls -l

• make sure the program can load its libraries using the command

ldd

• look what the problem is using the command

strace

Cannot do graphics

Warning: No xauth data; using fake authentication data for X11 forwarding.

=> have you changed your hostname?

My network connection is broken

• TroubleShooting network

Umount does not work

lsof | grep /mnt

Then kill the process.

root-Password is lost

Boot Linux with the parameter "init=/bin/bash" You get a root-shell. Enter:

mount -o remount, rw /
passwd
mount -o remount,ro /

and reboot

find out which files are accessed by a program

To find out which files are accessed by a program start it with

strace -e open program

Scripting

Use xtrace to get every line of a script shown before the line is executed.

If you want every line to be shown with evaluated values, write the following to the beginning of the script:

set -x

or -xv for verbose

TroubleShooting display

Get an problem with your display and you do not know if it is the graphics card, the monitor, or the display manager settings? See troubleshooting display

TroubleShooting network

See troubleshooting network

TroubleShooting sound

See troubleshooting sound.

TroubleShooting printers

See troubleshooting printers.