Admins Handbook

Compress a folder to a file with timestamp
tar cfvz /fil-$TIMESTAMP.tgz /etc

Postfix
If changed mail.cf, do a /etc/init.d/postfix reload
If changed /etc/postfix/virtual run this command: postmap hash:/etc/postfix/virtual
postmap /etc/postfix/transport

Copy a hard-drive
dd if=/dev/hd_originaldisk-partition of=/dev/hd_nydisk-partition

MySQL Backup
/usr/bin/mysqldump -A -uroot -p[myCode] > /andet/backup.sql

Delete a folder containing files
rm -rf /remove/this

Create an empty file
touch file-name

Disk-use of an folder
du -sh folder

Format disk
cfdisk /dev/hda

Extract tar.bz2 to a folder
tar xzf file.tar.bz2

NMAP scan to a file
nmap -sS -PT -PI -O -T 3 10.0.0.*>file.txt

Change file and folder rights
chown martin filename
chown -R martin:martin FileAndSubFolders

chmod
– user group other
– 4 2 1 4 2 1 4 2 1
– r w x r w x r w x

Boot script in Debian
/etc/rc.boot/
Remember: #!/bin/bash
on top of the text files.

Set date and time
ntpdate

Search inside files
find /www/test.local/www/ -name * | grep -lir VALID_AZ09 *

Create sources.list
http://debgen.simplylinux.ch/index.php

Show 30 largest folders
du -m /FOLDER | sort -nr | head -n 30
Size is in Megabyte