Linux

Linux is a free Unix-type operating system originally created by Linus Torvalds with the assistance of developers around the world. Developed under the GNU General Public License , the source code for Linux is freely available to everyone.

Links

• linux kernel
• Distributions

Rescue CDs

• Scientific Linux

• SystemRescueCd
• Knoppix

Checking resources

show what is doing most disk accesses

iotop 

IO statistics

iostat

CPU usage etc

top

Administration

• POSIX ACLS
• LVM
• Linux Software Raid
• Boot loader showdown: Getting to know LILO and GRUB

• Linux Power Management

FAQ

List hardware

• lshw
• dmidecode

Force reboot

I found sometimes 'reboot' and 'shutdown' don't work in virtual machines, in that case try:

#sync
echo s > /proc/sysrq-trigger
#optionally umount
echo u > /proc/sysrq-trigger
#reboot
echo b > /proc/sysrq-trigger