Linux Dummies 9th

Chapter 22
Ten Troubleshooting Tips
In This Chapter
▶ Dealing with frozen installations
▶ Changing your boot environment
▶ Recovering when you see a black-and-white text screen!
▶ Escaping a hung GUI
▶ Using multiple resolutions
Troubleshooting is like reading a mystery novel: You have some facts,
symptoms, and details, but you don’t know whodunit. You have to take
whatever information you have, work with that data, weigh the various possibilities,
and then narrow them to a single suspect. Finally, you need to test
your theory and prove that your suspect is the guilty party.
Troubleshooting problems in Linux (or any operating system) can encompass
many hardware and software issues. Whether the problem is the operating
system, the hardware, or a service giving you fits, you can use some basic
troubleshooting techniques to start your investigations:
✓ Document the problem. Write down any and all symptoms that the
system is showing, including actions you can and can’t do. Jot down any
information you see in error messages.
✓ Examine the Linux log files. You can find most of these in the /var/
log directory. Look for the word error.
✓ Compare your problem system with a working system running the
same distribution and version. Sometimes comparing configuration
files and settings may uncover the problem or narrow the possibilities.
✓ Check connections. Check to make sure that all the hardware is connected
properly and powered on. Verify that all cables and connections
are attached properly. There’s always someone, somewhere, accidentally
kicking a cable out of a wall connection.