This document provides an overview of various Linux basics including the VIM text editor, networking commands, SSH secure shell, SSH keys, package management, package dependencies, services, Apache web server configuration, MySQL database server, caching, and configuration management tools like Puppet, CFEngine, and Chef. It discusses installing and using the popular Wordpress content management system on a Linux server.

1. Linux Basics
Part 2

2. VIM Editor
• vi improved
• Installed on most Linux machines
• Can be a bit confusing at first...
oCheat sheets FTW
• Other popular editors:
oemacs
onano

3. Networking
• Commands:
o ifconfig
o netstat
o route
o ifup / ifdown
o traceroute
o mtr
• Configuration setup
different based on
distro
• DHCP vs. static

4. SSH: Secure Shell
• Secure Remote Shell
o Encrypted
• Replaced un-secure rsh, rlogin, and telnet
• Useful tricks
o Port forwarding
o SOCKS proxy server
o Remote command automation
o Remote X applications
o Copy files securely

5. SSH Keys
• Public/Private key authentication
• No password “over the wire”
• ssh-agent – “passwordless” logins
• ssh-keygen
• RSA vs DSA
• Remote script automation

6. Package Management
Contains files for a
package (binaries,
documentation, etc.),
install scripts, and
metadata about the
package
Picture © Flickr user 'retail-packaging'

7. Benefits of Packages
• Easy to manage (install, upgrade, remove)
• Central database tracks all installed
packages on a system
• yum/apt (or similar tools) handles
dependency resolution
• Package repositories make it easy to
find/install common software
• Included/official repos vs. external repos

8. Package Dependencies
• What does this package need in order
to run?
osome other package? A certain
(version of a) library?
• What does this package provide?
oie. binary, library, etc.
• Simplifies package installation

9. Some Examples
# Searching for a package
yum search php
apt-cache search php
# Installing a package
yum install php
apt-get install php
# List all files from a package
rpm -ql php
dpkg-query -L php
# Updating all packages
yum update
apt-get upgrade

10. Services
• Background
processes serving
something
• Examples: http,
email, mysql, etc
• Automatically start
when Linux boots
Picture © Lance Albertson

11. Serving a Website
• LAMP “stack”
• Apache
• PHP/Perl/etc
• Database

12. Apache: Web Server
• Easy to configure and use
• Very dynamic in uses
• Modular
• Widely used

13. Apache: virtual hosts
• Multiple websites on the same
server
• IP-based vs. Named-based

14. Mysql: Database server
• Most commonly used database with webapps
• /etc/my.cnf – config
• /var/lib/mysql – data files
• Other Databases:
o postgresql
o sqlite

15. Caching
• High Traffic sites
• Database caching
• Memcached
• Op-code caching
• Static content caching

16. Configuration Management
• Infrastructure programming
language
• Defining your infrastructure
• Puppet
• CFEngine
• Chef

17. Wordpress Install
• Setup MySQL & Apache
• Create Virtual Host
• Create Database & user
• Unpack tarball
• Go to website

18. Questions?
source: http://xkcd.com/456/