to track down what an intruder might have changed, either to repair the
damage or to try to catch the intruder by using computer forensics, but
rather plan to merely wipe everything clean and rebuild or reinstall the
system from scratch.Rebooting the System
You should use the shutdown command to reboot your system. The fastest
way to cleanly reboot Linux is to use the -r option and the word now:
Click here to view code image
matthew@seymour:~$ sudo shutdown -r now
You can also follow -r with the numeral zero ( 0 ), like this, to get the same
effect:
Click here to view code image
matthew@seymour:~$ sudo shutdown -r 0
Both rebooting and shutting down can have dire consequences if performed at
the wrong time (such as during backups or critical file transfers, which
arouses the ire of your system’s users). However, Linux-based operating
systems are designed to properly stop active system services in an orderly
fashion. Other commands you can use to shut down and reboot Linux are the
halt and reboot commands, but the shutdown command is more
flexible.
Commonly Used Commands and Programs
A number of programs and built-in shell commands are commonly used when
working at the command line. These commands are organized here by
category to help you understand the purpose of each category:
Managing users and groups—chage, chfn, chsh, edquota,
gpasswd, groupadd, groupdel, groupmod, groups,
mkpasswd, newgrp, newusers, passwd, umask, useradd,
userdel, usermod
Managing files and file systems—cat, cd, chattr, chmod, chown,
compress, cp, dd, fdisk, find, gzip, ln, mkdir, mksfs,
mount, mv, rm, rmdir, rpm, sort, swapon, swapoff, tar,
touch, umount, uncompress, uniq, unzip, zip