This Symptom databank aims to guide you to the appropriate trouble shooting guides based on the nature of the problem you are experiencing. Below are a number of common issues with background information and links to more detailed problem solving guides. A full list of technical guides can be found in the Kernel/Debugging section of the Kernel documentation.
To edit the Symptom databank see Kernel/Debugging/SymptomEdit.
I updated my system and it will no longer boot!
Unfortunately it is sometimes the case that your system will fail to boot due to changes within the kernel. It is important that when submitting bug reports about these types of failures that you include the appropriate debugging information that can help the kernel team resolve the issue. See the DebuggingKernelBoot guide for more information.
My display brightness will not change, how can I fix it?
Display brightness is influenced both by the brightness controls and the display brightness itself. An inability to control the brightness may be caused by either faulty controls not generating brightness changes, or by a lack of control off the displays backlight.
To analyse faulty keyboard controls see the Hotkeys/Troubleshooting.
To analyse faulty backlight control see the Kernel/Debugging/Backlight.
My system is reporting very high temperature, what can I do about this?
Temperature is normally managed by the BIOS on your system. Under some circumstances this can be affected by the system for example the workload on it. For some hints as to how to confirm you have a real issue and report any issues see Kernel/Debugging/HighTemperatures.
My multimedia keys (volume, brightness etc) do not function
The multimedia keys such as volume and brightness controls are often handled specially by your machines BIOS. If those keys are not triggering expected behaviour you should consult the Hotkeys/Troubleshooting guide.
I tried to suspend my machine and it apparently resumed immediately
If you have recently upgraded and not yet rebooted you are unable to suspend. You can determine this from the colour of the power menu item, if this is red then you need to restart your system (when convienient) before suspend is possible.
Otherwise you should refer to the DebuggingKernelSuspend guide.
I tried to suspend my machine and it did not turn off
This is often caused by the system hanging while attempting to suspend devices. Please refer to the DebuggingKernelSuspend guide.
I tried to suspend my machine and it would not wake up
Please refer to the DebuggingKernelSuspend guide.
I tried to suspend my machine and it returned me to the login screen
This could either indicate that you have been logged out during resume, else the machine may have rebooted. Please refer to the DebuggingKernelSuspend guide.
I was upgrading/updating my kernel and it did not work correctly
If you were performing an update either manually or via the update manager and you had problems with the kernel, you should follow the Kernel/DebuggingUpdateErrors guide.