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How To Setup A LAMP Server On Centos 6.0

lifeLinux — Fri, 26 Aug 2011 00:50:25 +0000

LAMP is essentially a server that runs Linux, Apache, MySQL and Php/Perl and is more commonly known as a LAMP server. This guide provides step-by-step instructions for installing a full-featured LAMP server on a CentOS 6 .0

1. Update system

Before proceeding to install, update the system with the following command

# yum update

2. Install and Configure the Apache Web Server

The Apache web server is the most popular server online, used on more than 70% of all servers connected to the World Wide Web. And there are good reasons for it: it’s free, it’s very stable, it delivers a great performance, it’s very customizable. To install the current version of the Apache web server use the following command

# yum install httpd

If you want to run Apache by default when the system boots, type the following command

# chkconfig httpd --level 2345 on

To start Apache for the first time, type the following command

# /etc/init.d/httpd start

3. Apache Web Server Security and Optimization

1. Disable any unnecessary apache modules, type the following command

# vi /etc/httpd/conf/httpd.conf

My example configuration is here

LoadModule auth_basic_module modules/mod_auth_basic.so
LoadModule auth_digest_module modules/mod_auth_digest.so
LoadModule authn_default_module modules/mod_authn_default.so
LoadModule authz_host_module modules/mod_authz_host.so
LoadModule authz_user_module modules/mod_authz_user.so
LoadModule authz_default_module modules/mod_authz_default.so
LoadModule include_module modules/mod_include.so
LoadModule log_config_module modules/mod_log_config.so
LoadModule env_module modules/mod_env.so
LoadModule mime_magic_module modules/mod_mime_magic.so
LoadModule expires_module modules/mod_expires.so
LoadModule deflate_module modules/mod_deflate.so
LoadModule headers_module modules/mod_headers.so
LoadModule setenvif_module modules/mod_setenvif.so
LoadModule mime_module modules/mod_mime.so
LoadModule status_module modules/mod_status.so
LoadModule autoindex_module modules/mod_autoindex.so
LoadModule info_module modules/mod_info.so
LoadModule negotiation_module modules/mod_negotiation.so
LoadModule dir_module modules/mod_dir.so
LoadModule actions_module modules/mod_actions.so
LoadModule alias_module modules/mod_alias.so
LoadModule rewrite_module modules/mod_rewrite.so

2. Optimize Timeout & KeepAlive
You need to control Timeouts & KeepAlive to improve server performance. Type the following command

# vi /etc/httpd/conf/httpd.conf

Find & Edit it as follows

Timeout 10
KeepAlive On
MaxKeepAliveRequests 200
KeepAliveTimeout 5

3. Optimize MPM (Multi-Processing Module)
Apache’s default installation of MPM Prefork. To optimize MPM Prefork, type the following command

# vi /etc/httpd/conf/httpd.conf

Find

Edit it as follows


    StartServers          5
    MinSpareServers      10
    MaxSpareServers      15
    ServerLimit         450
    MaxClients          450
    MaxRequestsPerChild   0

Which,

# StartServers: number of server processes to start
# MinSpareServers: minimum number of server processes which are kept spare
# MaxSpareServers: maximum number of server processes which are kept spare
# ServerLimit: maximum value for MaxClients for the lifetime of the server
# MaxClients: maximum number of server processes allowed to start
# MaxRequestsPerChild: maximum number of requests a server process serves

4. Enable Mod_rewite
To enable mod_rewirte, type the following command

# vi /etc/httpd/conf/httpd.conf

Find

Edit it as follows


    AllowOverride All
    Options -MultiViews -Indexes FollowSymlinks IncludesNoExec +Includes

    Order allow,deny
    Allow from all


    Order deny,allow
    Deny from all

5. Enable File Caching
Enabling file caching can greatly improve your site’s performance and speed. If you want to enable file caching, type the following command

# vi /etc/httpd/conf/httpd.conf

Find

Edit it as follows


    AllowOverride All
    Options -MultiViews -Indexes FollowSymlinks IncludesNoExec +Includes

    Order allow,deny
    Allow from all


    Order deny,allow
    Deny from all

  
	Header set Cache-Control "max-age=604800, public"

4. Install and Configure MySQL Database Server

MySQL Server is one of the most popular database servers in the world, especially for use with dynamic, content rich websites. To install MySQL database server use the following command

# yum install mysql mysql-server

After installing MySQL, I highly recommend to run mysql_secure_installation, a program that helps secure MySQL. Important points to note are:
1. Be sure that the root account has a secure password set.
2. Do not create an anonymous account, and if it exists, say “yes” to remove it.
3. If your web server and MySQL server are on the same machine, you should disable the network access.

If you want to run MySQL by default when the system boots, type the following command

# chkconfig mysqld--level 2345 on

To start MySQL for the first time, type the following command

# /etc/init.d/mysqld start

5. Installing and Configuring PHP

PHP is a general-purpose scripting language originally designed for web development to produce dynamic web pages. Many popular web applications like WordPress, Joomla, Drupal, OScommerce, Magento are written in PHP. To install PHP on CentOS use the following command

# yum install php53 php53-mysql

To create secure PHP configuration settings, type the following command

# vi /etc/php.ini

Find & Edit it as follows

allow_url_fopen = Off 
display_errors = Off 
display_startup_errors = Off 
log_errors = On 
error_reporting = E_ALL 
expose_php = Off 
magic_quotes_gpc = On 
magic_quotes_sybase = Off 
register_globals = Off
max_execution_time = 60
memory_limit = 64M

To prevent run PHP scripts with a different file extension, type the following command

# vi /etc/httpd/conf.d/php.conf

Find

AddHandler php5-script .php
AddType text/html .php

Replace it as follows


	AddHandler php5-script .php
	AddType text/html .php

Restart Apache to reload new configurations. Type the following command

# /etc/init.d/httpd restart

The post How To Setup A LAMP Server On Centos 6.0 appeared first on lifeLinux: Linux Tips, Hacks, Tutorials, Ebooks.

Using yum command on CentOS / RedHat

lifeLinux — Sat, 30 Apr 2011 07:27:48 +0000

yum is an interactive, automated update program which can be used for maintaining systems using rpm.

Synopsis

yum [options] [command] [package ...]

The following is a list of the most commonly used yum commands:

Install a package

yum install [package name]

Used to install the latest version of a package or group of packages. If no package matches the specified package name(s), they are assumed to be a shell glob, and any matches are then installed.

Update the specified packages

yum update [package name]

Used to update the specified packages to the latest available version. If no package name/s are specified, then yum will attempt to update all installed packages.

Check update

yum check-update

This command allows you to determine whether any updates are available for your installed packages. yum returns a list of all package updates from all repositories if any are available.

Remove a package

yum remove [package name]

Used to remove specified packages, along with any other packages dependent on the packages being removed.

Determine which packages provide a specific file or feature

yum provides [file name]

Find any packages containing the specified keyword

yum search [keyword]

This command is used to find any packages containing the specified keyword in the description, summary, packager and package name fields of RPMs in all repositories.

For a complete list of available yum commands, refer to man yum.

man yum

Sample outputs:

NAME
       yum - Yellowdog Updater Modified

SYNOPSIS
       yum [options] [command] [package ...]

DESCRIPTION
       yum  is an interactive, rpm based, package manager. It can automatically perform system updates, including dependency analysis and obsolete pro-
       cessing based on "repository" metadata. It can also perform installation of new packages, removal of old packages and  perform  queries  on  the
       installed  and/or  available  packages  among many other commands/services (see below). yum is similar to other high level package managers like
       apt-get and smart.

       While there are some graphical interfaces directly to the yum code, more recent graphical interface development is happening with PackageKit and
       the gnome-packagekit application.

       command is one of:
        * install package1 [package2] [...]
        * update [package1] [package2] [...]
        * check-update
        * upgrade [package1] [package2] [...]
        * remove | erase package1 [package2] [...]
        * list [...]
        * info [...]
        * provides | whatprovides feature1 [feature2] [...]
        * clean [ packages | headers | metadata | dbcache | all ]
        * makecache
        * groupinstall group1 [group2] [...]
        * groupupdate group1 [group2] [...]
        * grouplist [hidden] [groupwildcard] [...]
        * groupremove group1 [group2] [...]
        * groupinfo group1 [...]
        * search string1 [string2] [...]
        * shell [filename]
        * resolvedep dep1 [dep2] [...]
        * localinstall rpmfile1 [rpmfile2] [...]
        * localupdate rpmfile1 [rpmfile2] [...]
...

Example: Install LAMP with single command by yum

Enter the following command:

yum install httpd mysql mysql-server php

The post Using yum command on CentOS / RedHat appeared first on lifeLinux: Linux Tips, Hacks, Tutorials, Ebooks.

chkconfig Command

lifeLinux — Tue, 23 Nov 2010 17:24:13 +0000

chkconfig provides a simple command-line tool for maintaining the/etc/rc[0-6].d directory hierarchy by relieving system administrators of the task of directly manipulating the numerous symbolic links in those directories.

chkconfig has five distinct functions: adding new services for management, removing services from management, listing the current startup information for services, changing the start-up information for services, and checking the start-up state of a particular service.

Synopsis

chkconfig --list [name]
chkconfig --add name
chkconfig --del name
chkconfig [--level levels] name 
chkconfig [--level levels] name

Example

List status for all services

chkconfig --list

List status for test service

chkconfig --list test

Add service called test

chkconfig --add test

Delete service called test

chkconfig --del test

Turn on & Turn off service

chkconfig --level 3 5 httpd off

The command above will turn off httpd service in run levels 3 and 5.

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