the difference between single- and multi-user modes
some useful disk-utilization utilities
installing software
how to create a new file system
how to add and delete user accounts
an overview of how a device is installed
configuring a network interface
tunable kernel parameters
some common security problems
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Quiz
1.
Why should you shut down a Linux system instead of simply turning it off?
2.
Why do most versions of Linux now use a "shadow" password file in addition to the normal /etc/passwd file?
3.
Why is it better to use su to become the super-user than to simply log in as "root"?
4.
How can you put Linux into single-user mode?
5.
Which files must be modified when you add a new user?
6.
What does the ifconfig command do?
7.
Describe the "Trojan horse" technique for capturing a super-user password.
Exercises
1.
Try using cpio and tar to transfer some files to and from whatever removable media are available on your system (or to a file in /tmp if no removable media are available). Which of these utilities do you prefer? Why? [level: easy]
2.
Use du to examine your disk usage. Write a script that prints out the full pathnames of your files that are over a specified size. [level: medium]
3.
Fill in the functionality of the skeleton script you wrote in Exercise 1 of Chapter 7, "The Korn Shell," so that it will perform the system administration tasks in your menu-driven interface. Useful tasks to automate include:
automatic deletion of core files
automatic warnings to users that use a lot of CPU time or disk space
automatic archiving
[level: medium]
Project
1.
Find an optional package (in RPM format) on your Linux distribution CD or on the Internet and install it on your system. [level: easy]
2.
Explore the /proc file system and find out the kind of data a normal user can access. Why is it useful to be able to read this data? [level: medium]
