Apache 2

Requirements

Before going through this tutorial, I recommend you to setup:

• MySQL server
• SSL infrastructure and create a server certificate - see SSL server
• LDAP server

Installation

Apache 2

This will install web server + PHP + Perl + all required libraries.

Apache2 core

apt-get install apache2 apache2-mpm-prefork apache2-utils ssl-cert

Additional libraries

apt-get install libapache2-mod-fcgid libruby

Doc

apt-get install apache2-doc

Perl

apt-get install libapache2-mod-perl2 libapache2-mod-perl2-doc

PHP 5

Core

apt-get install libapache2-mod-php5 php5 php5-common

Module PHP5

apt-get install php5-curl php5-dev php5-gd php-pear php5-imagick php5-imap php5-mcrypt 
apt-get install php5-memcache php5-mhash php5-mysql php5-snmp php5-xmlrpc php5-xcache php5-curl php5-xsl

Additional libs

apt-get install php5-cli php5-cgi php-pear php-auth php5-mcrypt mcrypt

Image Magick

apt-get install php5-imagick imagemagick

Firewall

You have to open the following ports:

• Port 80 = HTTP
• Port 443 = HTTPS

$IPTABLES -A INPUT -p tcp -m state -i eth0 --dport 80 -j ACCEPT
$IPTABLES -A INPUT -p tcp -m state -i eth0 --dport 443 -j ACCEPT

Restart the firewall

/etc/init.d/firewall restart

PHP 5

Edit config file:

vim /etc/php5/apache2/php.ini

Add / uncomment the following lines in Dynamic extensions area (~ line 865)

• extension=mysql.so
• extension=gd.so

Apache 2 configuration # Multi-threading

MPM prefork

This manage processes

• Max clients = nb of max simultaneous requests that the server can handle
• Server limit = max nb of process that the server can handle
• Start servers = nb of process to create on server start
• Min / Max spare servers = nb of min / max process listening for incoming request
• Max request per child = nb of requests that each process can execute

vim /etc/apache2/apache2.conf

Let default values; put a limit to MaxRequestsPerChild at 100 000

MPM worker

This manage threads. Threads are executed within a specific process. All process’ threads share the same context and global variables.

vim /etc/apache2/apache2.conf

Let default values; put a limit to MaxRequestsPerChild at 10 000

Apache 2 configuration # Virtual host

Preparation

Initialize configuration

cd /etc/apache2/sites-available/

Create target directory

mkdir -p /var/www/myServer

Prepare the log files

mkdir -p /var/log/apache2/myServer
touch /var/log/apache2/myServer/access.log
touch /var/log/apache2/myServer/error.log
chmod -R 660 /var/log/apache2/myServer/*
chown -R www-data:www-data /var/log/apache2/myServer/*

Configuration

Init configuration

cp /etc/apache2/sites-available/000-default.conf /etc/apache2/sites-available/myServer.conf

Edit configuration

vim /etc/apache2/sites-available/myServer

To begin the virtual host, write the following lines: → Adjust the settings to your own configuration

<VirtualHost 192.168.0.100:80>		  → Choose the best options for your needs
<VirtualHost *:80>

	ServerName		myServer
	ServerAlias		www.myServer *.myServer
	ServerAdmin		webmaster@domain
	
	# Logs settings
	LogLevel		Warn
	CustomLog		{APACHE_LOG_DIR}/myServer/access.log combined
	ErrorLog		{APACHE_LOG_DIR}/myServer/error.log

	# Root folder properties
	DocumentRoot	/var/www/myServer
	<Directory />
		Options FollowSymLinks 
		AllowOverride None
	</Directory>
        <Directory /var/www/myServer />
		Options Indexes FollowSymLinks MultiViews
		AllowOverride None
		Order allow,deny
		allow from all
	</Directory>

	# Scripts CGI
	# [ required for PHP 5 ]
	ScriptAlias /cgi-bin/ /var/www/cgi-bin
	<Directory "/var/www/cgi-bin">
		AllowOverride None
		Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch
		Order allow,deny
		Allow from all
	</Directory>

</VirtualHost>

Activation of a Virtual Host

To activate a Virtual Host, just type

a2ensite  myServer

Then, restart your web server

/etc/init.d/apache2 restart

Apache 2 configuration # SSL Virtual host

Create SSL certificate

First of all, you need to create a server certificate. Cf. SSL dedicated document → Create a new server certificate

>> see SSL server

Enable SSL module

Create symlinks for server certificate

ln -s /srv/ssl/certs/myServer.cert.pem /etc/apache2/webServer.pem
ln -s /srv/ssl/private/myServer.nopass.key /etc/apache2/webServer.key

Activate the SSL module

a2enmod ssl

Prepare virtual host (optional)

Create virtual host folder

mkdir -p /var/www/myServer-ssl
cp /var/www/index.html /var/www/myServer-ssl
chown -R www-data:www-data /var/www/myServer-ssl

Prepare the log files (optional)

mkdir -p /var/log/apache2/myServer-ssl
touch /var/log/apache2/myServer-ssl/error.log
touch /var/log/apache2/myServer-ssl/access.log
chmod 660 /var/log/apache2/*
chown root:www-data /var/log/apache2/*

Virtual host declaration

You have 2 possibilities:

• Update your current virtual host
• Create a new one, only for the SSL virtual host

New virtual host: Init configuration

cp /etc/apache2/sites-available/default-ssl /etc/apache2/sites-available/myServer-ssl

Edit V.Host configuration

vim /etc/apache2/sites-available/myServer-ssl

Then, you will need to edit the Virtual Host configuration file:

vim /etc/apache2/sites-availables/virtualHostName

!! Adjust the settings to your own configuration

# Secure web server
<VirtualHost _default_:443>
<VirtualHost 192.168.0.100:443>		   → Choose the best options for your needs
<VirtualHost *:443>

	ServerName		myServer
	ServerAlias		www.myServer *.myServer
	ServerAdmin		webmaster@domain
	
	# Logs settings
	LogLevel		Warn
	CustomLog		{APACHE_LOG_DIR}/myServer-ssl/access.log combined
	ErrorLog		{APACHE_LOG_DIR}/myServer-ssl/error.log

	# Root folder properties
	DocumentRoot	/var/www/myServer-ssl

        # Enable SSL
        SSLEngine               	On
        SSLCertificateFile      	/etc/apache2/webServer.pem
        SSLCertificateKeyFile   	/etc/apache2/webServer.key

        # Root directory properties
        <Directory /var/www/ssl />
            Options Indexes FollowSymLinks MultiViews
            AllowOverride None
            Order allow,deny
            allow from all
        </Directory>

        ##########################
        # ALIAS AND REDIRECTIONS #
        ##########################

</VirtualHost>

Enable site

a2ensite myServer-ssl

Restart the web server

/etc/init.d/apache2 restart

Accept auto-signed certificate

Go to https://myServer/certs/ Cf SSL document to get installation details

Apache 2 configuration # Redirect HTTP to HTTPS

The safer way to redirect HTTP to HTTPS is use to adjust the virtual host configuration.

Edit configuration

vim /etc/apache2/sites-available/myServer

Make it looks like:

<VirtualHost *:80>
	ServerAdmin guillaume@qin-diaz.com

	ServerName dev.daxiongmao.eu
	ServerAlias *.dev.daxiongmao.eu dev.qin-diaz.com www.dev.qin-diaz.com

	### LOG ###
	ErrorLog ${APACHE_LOG_DIR}/daxiongmao/error.log
	LogLevel warn
	CustomLog ${APACHE_LOG_DIR}/daxiongmao/access.log combined
	
	## Redirect all traffic to HTTPS website
	redirect permanent / https://myServer/
	
	## No need of a document root anymore as everything is redirect
	
</VirtualHost>

You can remove:

• Document root
• CGI url
• All the alias

Restart your server

service apache2 restart

Apache 2 # redirections using mod_proxy

Thanks to Julien Rialland for his insight regarding this part!

Principle

The proxy module allow you to redirect remote user to a specific server that can be host on a different machine or port through a clear URL.

Current limits

Some application are not available from outside…

• For security reasons [default URL is not allowed]

• Due to network issues

Proxy module role

The proxy module allow you to provide access through transparent redirection.

It relies on:

• Already open port (80 or 443)
• Redirection rule
• Each service URL must be unique
• The target service must be reachable by the web server

As you can see on the following example, the previous services will be accessible using some dedicated URL. Remote “http://myServer/myService” will redirect to “http://localhost:8081”

→ The mod_proxy is none intrusive. You don’t have to change anything is the orginal service configuration. Apache2 will handle all the transformations.

Proxy / redirect / rewrite

When Apache2 receive a request it will be process in the following order:

So, even if you enable a full redirection to HTTPS you can still use some HTTP service through mod_proxy.

Enable proxy module

a2enmod proxy proxy_http proxy_ajp

Configure proxy redirections

You can configure the redirections in 2 ways:

• Through your virtual host configuration
• Through the module configuration file

Module configuration file

You have to edit / create the configuration file.

vim /etc/apache2/mods-enabled/proxy.conf

Virtual host

Just edit again your previous V.Host:

vim /etc/apache2/sites-available/myServer.conf

Proxy declaration

Adjust the file to:

<VirtualHost *:80>
...
	## Proxy
	ProxyVia On
        ProxyPreserveHost On
        <Proxy *>
             AddDefaultCharset off
             Order deny,allow
             Allow from all
	</Proxy>

        #### To allow some URLs to go through without being proxy ####
	# Active MQ REST web-service, required for hawt.io management
	ProxyPass /activemq-api http://localhost:8161/activemq-api
	ProxyPassReverse /activemq-api http://localhost:8161/activemq-api 	
</VirtualHost>

<VirtualHost *:443>
...
	## Proxy
	ProxyVia On
        ProxyPreserveHost On
        <Proxy *>
             AddDefaultCharset off
             Order deny,allow
             Allow from all
             Satisfy Any
        </Proxy>

	RewriteEngine On

	########################
	# Allow some URLs to go through without being proxy
	########################
        # URL to discard => Classic HTTP services
	ProxyPass /menu !
	ProxyPass /maintenance !

	# PhpMyAdmin
	<Location /phpmyadmin>
		Order allow,deny
		Allow from 127.0.0.1 192.168.1.0/24 193.12.118.194 90.83.80.64/27 90.83.80.123 77.68.140.115 91.121.17.114 193.12.118.196
		Require all granted 
		ProxyPass !
	</Location>

	########################
	# Proxy redirections
	########################

	# Proxy to a Java application running over Tomcat
	ProxyPass /webdav/ ajp://localhost:8009/webdav/
	ProxyPassReverse /webdav/ ajp://localhost:8009/webdav 	

	# Proxy to a Java application running over Tomcat, with IP filter
	<Location /manager>
		Order allow,deny
		Allow from 127.0.0.1 192.168.1.0/24 193.12.118.194 90.83.80.64/27 90.83.80.123 77.68.140.115 91.121.17.114 193.12.118.196
		ProxyPass ajp://localhost:8009/manager/
		ProxyPassReverse ajp://localhost:8009/manager/
	</Location>

        # Proxy to another server
        ProxyPass /jira http://192.168.1.12:8080/jira
        ProxyPassReverse /jira http://192.168.1.12:8080/jira
</VirtualHost>


#
# Instead of "VirtualHost" you can use "IfModule" if you're editing the "proxy.conf" file
#
<IfModule mod_proxy.c>

</IfModule>

Some notes:

• Do NOT put a / after the target URL
• Do NOT use / as ProxyPass source, use the previous redirect permanent instead

Apply changes and test result

service apache2 restart

Navigate to http://myServer/artifactory

Apache 2 configuration # LDAP authentication

Enable LDAP module

a2enmod authnz_ldap
service apache2 restart

Configuration

You can use the following settings inside a “.htaccess” or “VirtualHost” configuration:

Edit configuration

vim /etc/apache2/sites-available/myServer

Adjust your virtual-host like that:

# LDAP protected directory
<Directory /var/www/ssl/secure>
   Options Indexes FollowSymLinks MultiViews
   AllowOverride None
   Order allow,deny
   allow from all

   AuthType basic
   AuthName "Secure area"	
   AuthBasicProvider ldap
   AuthLDAPUrl "ldap://localhost:389/{LDAP ou=,dc=}?uid"
   Require valid-user

   # example
   # AuthLDAPBindDN "cn=admin,dc=dev,dc=daxiongmao,dc=eu"
   # AuthLDAPUrl "ldap://localhost:389/ou=people,dc=dev,dc=daxiongmao,dc=eu?uid"

</Directory>

Secure all the website

You have to adjust you document root like that:

<VirtualHost _default_:443>

	# Restrict access to document root
	DocumentRoot /var/www/daxiongmao-ssl
	<Directory />
		Options FollowSymLinks
		AllowOverride None
		Order allow,deny
		deny from all
	</Directory>
	<Directory /var/www/daxiongmao-ssl>
		Options Indexes FollowSymLinks MultiViews
		AllowOverride None
		Order allow,deny
		allow from all
		
		AuthType basic
		AuthName "Secure area"	
		AuthBasicProvider ldap
		AuthLDAPUrl "ldap://localhost:389/ou=people,dc=dev,dc=daxiongmao,dc=eu?uid"
		Require valid-user
	</Directory>
[…]

Apache 2 configuration # Advanced configuration

Enable redirections

Mod rewrite allows you to redirect source URL to another one.

Enable module

a2enmod rewrite

Alias redirection

Edit configuration

vim /etc/apache2/sites-available/myServer

HTTP virtual host = redirect to HTTPS

<VirtualHost *:80>
	RewriteRule ^/myAlias(/.*|$)    https://%{HTTP_HOST}/myAlias$1 [L,R]
	<Location /myAlias >
		order deny,allow
		deny from all
                # Only allow specific IP@
                # allow from 127.0.0.1 192.168.0.0/255.255.255.0	
                allow from all
	</Location>
</VirtualHost>

HTTPS virtual host = service declaration

<VirtualHost _default_:443>
	# PHPSecInfo
	Alias 	/myAlias   /var/www/myAlias
	<Location /myAlias >
		order deny,allow
		deny from all
                # Only allow specific IP@
                # allow from 127.0.0.1 192.168.0.0/255.255.255.0	
                allow from all
        </Location>
</VirtualHost>

Reload your configuration

/etc/init.d/apache2 reload

Redirect HTTP to HTTPS

This is not the recommended method. You should use the previous method instead.

<VirtualHost *:80>
	ServerAdmin guillaume@qin-diaz.com
	ServerName dev.daxiongmao.eu
	ServerAlias *.dev.daxiongmao.eu dev.qin-diaz.com www.dev.qin-diaz.com

	### LOG ###
	ErrorLog ${APACHE_LOG_DIR}/daxiongmao/error.log
	LogLevel warn
	CustomLog ${APACHE_LOG_DIR}/daxiongmao/access.log combined
	
	## Redirect all traffic to HTTPS website
        RewriteEngine On

        # This checks to make sure the connection is not already HTTPS
        RewriteCond %{HTTPS} !=on

        # This rule will redirect users from their original location, 
        # to the same location but using HTTPS.
        RewriteRule ^/?(.*) https://%{SERVER_NAME}/$1 [R,L]
	
	## No need of a document root anymore as everything is redirect
	
</VirtualHost>

Module configuration

Create the module configuration file

vim /etc/apache2/conf.d/rewrite.conf

Copy / paste this configuration (adjust to your own settings!)

   RewriteEngine On
   # --------------------- SECURITY RULES (JOOMLA) ------------------------ #
   ## End of deny access to extension xml files
   RewriteCond %{QUERY_STRING} mosConfig_[a-zA-Z_]{1,21}(=|\%3D) [OR]
   # Block out any script trying to base64_encode crap to send via URL
   RewriteCond %{QUERY_STRING} base64_encode.*\(.*\) [OR]
   # Block out any script that includes a <script> tag in URL
   RewriteCond %{QUERY_STRING} (\<|%3C).*script.*(\>|%3E) [NC,OR]
   # Block out any script trying to set a PHP GLOBALS variable via URL
   RewriteCond %{QUERY_STRING} GLOBALS(=|\[|\%[0-9A-Z]{0,2}) [OR]
   # Block out any script trying to modify a _REQUEST variable via URL
   RewriteCond %{QUERY_STRING} _REQUEST(=|\[|\%[0-9A-Z]{0,2})
   # Send all blocked request to homepage with 403 Forbidden error!
   RewriteRule ^(.*)$ index.php [F,L]
   # --------------------- SECURITY RULES (PERSONAL) ------------------------ #
   ## DENY REQUEST BASED ON REQUEST METHOD ###
   RewriteCond %{REQUEST_METHOD} ^(TRACE|TRACK|OPTIONS|HEAD)$ [NC]
   RewriteCond %{REQUEST_METHOD} (GET|POST) [NC]
   RewriteRule ^.*$ - [F]
   # Eviter les failles de securite
   RewriteCond %{QUERY_STRING} ^(.*)http(\:|\%3A)(.*)$
   RewriteCond %{QUERY_STRING} mosConfig_ [NC,OR]
   RewriteCond %{QUERY_STRING} ^(.*)(%3C|<)/?script(.*)$ [NC,OR]
   RewriteCond %{QUERY_STRING} ^(.*)(%3D|=)?javascript(%3A|:)(.*)$ [NC,OR]
   RewriteCond %{QUERY_STRING} ^(.*)document\.location\.href(.*)$ [NC,OR]
   RewriteCond %{QUERY_STRING} ^(.*)base64_encode(.*)$ [NC,OR]
   RewriteCond %{QUERY_STRING} ^(.*)GLOBALS(=|[|%[0-9A-Z]{0,2})(.*)$ [NC,OR]
   RewriteCond %{QUERY_STRING} ^(.*)_REQUEST(=|[|%[0-9A-Z]{0,2})(.*)$ [NC,OR]
   RewriteCond %{QUERY_STRING} ^(.*)(SELECT|INSERT|DELETE|CHAR\(|UPDATE|REPLACE|LIMIT)(.*)$
   # Eviter les erreurs basiques
   RewriteCond %{QUERY_STRING} \.\.\/    [NC,OR]
   RewriteCond %{QUERY_STRING} boot\.ini [NC,OR]
   RewriteCond %{QUERY_STRING} tag\=     [NC,OR]
   RewriteCond %{QUERY_STRING} ftp\:     [NC,OR]
   RewriteCond %{QUERY_STRING} http\:    [NC,OR]
   RewriteCond %{QUERY_STRING} https\:   [NC,OR]
   RewriteCond %{QUERY_STRING} mosConfig [NC,OR]
   RewriteCond %{QUERY_STRING} ^.*(\(|\)|<|>|'|"|\?|\*).* [NC,OR]
   RewriteCond %{QUERY_STRING} ^.*(%22|%27|%3C|%3D|%3E|%7B|%7C).* [NC,OR]
   RewriteCond %{QUERY_STRING} ^.*(%0|%A|%B|%C|%D|%F|127\.0).* [NC,OR]
   RewriteCond %{QUERY_STRING} ^.*(globals|encode|localhost|loopback).* [NC,OR]
   RewriteCond %{QUERY_STRING} ^.*(select|insert|union|declare|drop).* [NC]
   RewriteRule ^(.*)$ - [F,L]

   # Ban Typical Vulnerability Scanners and others
   # Kick out Script Kiddies
   RewriteCond %{HTTP_USER_AGENT} ^(java|curl|wget).* [NC,OR]
   RewriteCond %{HTTP_USER_AGENT} ^.*(libwww-perl|curl|wget|python|nikto|wkito|pikto|scan|acunetix).* [NC,OR]
   RewriteCond %{HTTP_USER_AGENT} ^.*(winhttp|HTTrack|clshttp|archiver|loader|email|harvest|extract|grab|miner).* [NC,OR]
   # Eviter les programmes de Zombies
   RewriteCond %{HTTP_USER_AGENT} ^Anarchie [OR]
   RewriteCond %{HTTP_USER_AGENT} ^ASPSeek [OR]
   RewriteCond %{HTTP_USER_AGENT} ^attach [OR]
   RewriteCond %{HTTP_USER_AGENT} ^autoemailspider [OR]
   RewriteCond %{HTTP_USER_AGENT} ^Xaldon\ WebSpider [OR]
   RewriteCond %{HTTP_USER_AGENT} ^Xenu [OR]
   RewriteCond %{HTTP_USER_AGENT} ^Zeus.*Webster [OR]
   RewriteCond %{HTTP_USER_AGENT} ^Zeus
   RewriteRule ^.* - [F,L]

   # Allow the robots to reference our website
   RewriteCond %{HTTP_USER_AGENT} !^Googlebot [NC]
   RewriteCond %{HTTP_USER_AGENT} !^Googlebot-Image [NC]
   RewriteCond %{HTTP_USER_AGENT} !^Googlebot-Mobile [NC]
   RewriteCond %{HTTP_USER_AGENT} !^Msnbot [NC]
   RewriteCond %{HTTP_USER_AGENT} !^Mediapartners-Google [NC]

   # Keep request without referer
   RewriteCond %{HTTP_REFERER} !^$

   # To allow your pictures to be displayed on Google
   RewriteCond %{HTTP_REFERER} !^http://.*google\.(comŠ(co\.)?[a-z]{2})/
   # To forbid the copy of your pictures to anyone else : display an other image !
   RewriteRule .*\.(jpe?g|gif|bmp|png)$ /images/hotlinkis.jpg [L]

Take changes into account

You have to restart the server to use this settings

service apache2 restart

Ports number

You can change the Apache2 server ports

vim /etc/apache2/ports.conf

Edit

# HTTP
Listen 80
# HTTPS 
Listen 443

Restricted access

Edit configuration

vim /etc/apache2/sites-available/myServer

If your server is directly accessible on Internet: you should protect it!

# Disable access to the entire file system except for the directories that
# are explicitly allowed later.
#
<Directory />
        AllowOverride None
        Order Deny,Allow
        Deny from all
</Directory>

# Protect .htacess files
<Files ~ "^\.ht">
    Order allow,deny
    Deny from all
</Files>

Be discreet!

Check the current server status using a simple PHP info file

Do not gives details about your configuration to outsiders.

vim /etc/apache2/conf.d/security

Set the following settings

#### Ask your server to be more discret!
# ServerTokens
# Set to one of:  Full | OS | Minimal | Minor | Major | Prod
ServerTokens Prod

ServerSignature Off
TraceEnable Off

Restart Apache2

service apache2 restart

Re-run PHP info, you should have less information.

Apache 2 and PHP5: Secure your installation!

PHP Security Info

If you want to test your PHP security, you can use the PHPSecInfo tool, available at: http://phpsec.org/projects/phpsecinfo/index.html

Installation

cd /tmp
wget http://phpsec.org/projects/phpsecinfo/phpsecinfo.zip
unzip phpsecinfo.zip
mv phpsecinfo-Version phpsecinfo
mv phpsecinfo/ /var/www
cd /var/www
chown -R www-data:www-data phpsecinfo

Virtual host configuration

Edit configuration

vim /etc/apache2/sites-available/myServer

!! For security reason: DO NOT use 'phpsecinfo' as alias. It's too easy to guess.

<VirtualHost *:80>
	# Advanced redirection – Only allow specific IP @
	RewriteRule ^/phpsec(/.*|$)    https://%{HTTP_HOST}/phpsec$1 [L,R]
	<Location /phpsec >
		order deny,allow
		deny from all
                # Only allow specific IP@
                # allow from 127.0.0.1 192.168.0.0/255.255.255.0	
                allow from all
	</Location>
</VirtualHost>

<VirtualHost _default_:443>
	# PHPSecInfo
	Alias 	/phpsec   /var/www/phpsecinfo
	<Location /phpsec >
		order deny,allow
		deny from all
                # Only allow specific IP@
                # allow from 127.0.0.1 192.168.0.0/255.255.255.0	
               allow from all
         </Location>
</VirtualHost>

Reload your configuration

/etc/init.d/apache2 reload

Run the test

To asset your current installation you can run the test: https:// myServer/phpsec

Improve security

PHP5 sessions and temp files

Create specific directory to store the sessions and temp files:

mkdir -p /etc/php5/temp
mkdir -p /etc/php5/session
chown -R www-data:root /etc/php5/temp
chown -R www-data:root /etc/php5/session
chmod -R 770 /etc/php5/session
chmod -R 770 /etc/php5/temp

Edit the configuration file

vim /etc/php5/apache2/php.ini

line 798 → upload_tmp_dir = /etc/php5/temp line 1409 → session.save_path = "/etc/php5/session"

PHP5 tweak

vim /etc/php5/apache2/php.ini

line 261 → expose_php = Off line 480 → display_errors=Off line 675 → post_max_size=256K line 814 → allow_url_fopen=Off

DO NOT enable the open_basedir (even if the test say so! It’s a troublesome setting)

Restart your server to load the changes:

service apache2 restart

Re-run the test. Then:

• Ignore the open_basedir and upload_tmp_dir alerts, if any.
• You can enable some specific options with a .htaccess file

Change Apache 2 UID

Do not change the UID if you already have install web programs such as phpldapadmin or phpmyadmin, cacti, ...

Change the Apache UID

vim /etc/group

Change www-data UID

    www-data:x:10033:

Change the Apache GID

 
vim /etc/passwd

Change the group settings

	www-data:x:10033:10033:www-data:/var/www:/bin/false

Apply modifications

chown -R www-data:www-data /var/www/*
chown -R www-data:root /etc/php5/*

To take on the modifications you have to reboot your server.

Avoid DOS attacks

Source: Linux mag’ – Hors serie Apache2

You can protect your server from Denial Of Service (DOS) attacks through mod_evasive

apt-get install libapache2-mod-evasive

Prepare log directory

mkdir /var/log/apache2/mod_evasive
chown -R www-data:www-data  /var/log/apache2/mod_evasive

Enable module

a2enmod mod-evasive

Configuration

Create the configuration file

vim /etc/apache2/conf.d/mod_evasive.conf

Put:

# Mod evasive configuration
# Based upon Linux Mag 
<IfModule mod_evasive20.c>
	DOSHashTableSize 3097 

	# Limit user to 5 pages per 2 seconds
	DOSPageCount 5
	DOSPageInterval 2 

	# No more than 100 HTTP request per second (HTML, CSS, images, …) 
	DOSSiteCount 100
	DOSSiteInterval 1

	# Block client for 300 seconds
	DOSBlockingPeriod 300 
	# Send alert email
	#DOSEmailNotify "admin@myDomain" 

	# Log directory
	DOSLogDir "/var/log/apache2/mod_evasive" 

	# Command to execute on ban
	#DOSSystemCommand "/sbin/iptables -I INPUT -s %s -j DROP"

	# Ignore following IP and networks
	DOSWhiteList 127.0.0.1 
	#DOSWhitelist 66.249.65.*
<IfModule mod_evasive20.c>

DosHashTableSize = Size of the hash table.

• The greater, the more memory is required but the faster it is! The value must be a prime number

Apply changes

service apache2 restart

Apache2 configuration # Improve server performances

Mod deflate: improved the bandwidth

To improve the bandwidth, you can compress pages and type of content.

=> You can improved your bandwidth from 20 to 30%.

To do so, you need a specific module for Apache: mod_deflate

a2enmod deflate
touch /var/log/apache2/deflate.log
chown www-data:www-data /var/log/apache2/deflate.log
chmod 740 /var/log/apache2/deflate.log

Edit your web server configuration file:

vim /etc/apache2/conf.d/deflate.conf

Add the following lines:

### Bandwidth optimization
<IfModule mod_deflate.c>
	AddOutputFilterByType DEFLATE text/html text/plain text/xml text/javascript text/css application/x-javascript
	DeflateFilterNote deflate_ratio
	LogFormat "%v %h %l %u %t \"%r\" %>s %b"
	CustomLog /var/log/apache2/deflate.log vhost_with_deflate_info
</IfModule>

Restart your web server:

/etc/init.d/apache2 restart

Mod expires: use the cache of your clients

Another way to improve performances and bandwidth: use the client's cache.

To do so, you need a specific module for Apache: mod_expires

a2enmod expires

Edit your web server configuration file:

vim /etc/apache2/expires.conf

Add the following lines

#### Client's cache settings
<IfModule mod_expires.c>
	ExpiresActive on
	# set the default to 24 hours
	ExpiresDefault "access plus 24 hours"
	# cache shockwave-flash for 2 weeks (days | weeks | mounths | years)
	ExpiresByType application/x-shockwave-flash "access plus 2 weeks"
	ExpiresByType flv-application/octet-stream "access plus 3 days"
	# cache common graphics for 3 days
	ExpiresByType image/jpg "access plus 2 weeks"
	ExpiresByType image/gif "access plus 2 weeks"
	ExpiresByType image/jpeg "access plus 2 weeks"
	ExpiresByType image/png "access plus 2 weeks"
	# cache CSS for 24 hours
	ExpiresByType text/css "access plus 24 hours"
</IfModule>

Restart your web server:

/etc/init.d/apache2 restart