Fedora® 11 and Red Hat® Enterprise Linux® Bible

Chapter 12. Automating System Tasks

In This Chapter

• Understanding shell scripts

• System initialization

• System startup and shutdown

• Scheduling system tasks

You'd never get any work done if you typed every command that needs to be run on your Fedora or RHEL system when it starts. Likewise, you could work more efficiently if you grouped together sets of commands that you run all the time. Shell scripts can handle these tasks.

A shell script is a group of commands, functions, variables, or just about anything else you can use from a shell. These items are typed into a plain-text file. That file can then be run as a command. Fedora and RHEL use system initialization shell scripts during system startup to run commands needed to get things going. You can create your own shell scripts to automate the tasks you need to do regularly.

This chapter provides a rudimentary overview of the inner workings of shell scripts and how they can be used. You learn how shell scripts are responsible for the messages that scroll by on the system console during booting and how simple scripts can be harnessed to a scheduling facility (such as cron or at) to simplify administrative tasks.

You also learn to fine-tune your machine to start the most appropriate run level and to run only services you need. With that understanding, you'll be able to personalize your computer and cut down on the amount of time you spend repetitively typing the same commands.

Understanding Shell Scripts

Have you ever had a task that you needed ...