To keep your system in optimum shape, you need to be able to monitor it closely. Such monitoring is imperative in a corporate environment where uptime is vital and any system failures can cost real money. Whether it is checking processes for any errant daemons, or keeping a close eye on CPU and memory usage, Ubuntu provides a wealth of utilities designed to give you as little or as much feedback as you want. In this chapter, we look at some of the basic monitoring tools, along with some tactics designed to keep your system up longer. Some of the monitoring tools cover network connectivity, memory, and hard drive usage, but all should find a place in your sysadmin toolkit. Finally you will learn how to manipulate active system processes using a mixture of graphical and command-line tools.

Console-Based Monitoring

Those familiar with UNIX system administration already know about the ps or process display command commonly found on most flavors of UNIX. Because Linux is closely related to UNIX, it also benefits from this command and enables you to quickly see the current running processes on the system as well as who owns them and how resource-hungry they are.

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