Package:Apache

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www-servers/apache


Current Maintainer(s):polynomial-c@gentoo.org
Source Repository:Gentoo Portage Tree
Homepage

Summary: The Apache Web Server

Use Flags

suexec
Install suexec with apache
static
Link in apache2 modules statically rather then plugins
apache2_modules_access_compat
Group authorizations based on host (name or IP address). Available as a compatibility module with previous versions.
apache2_modules_authn_core
Provides core authentication capabilities common to all authentication providers (functionality provided by authn_alias in previous versions).
apache2_modules_authz_core
Provides core authorization capabilities to various authorization/authorization modules, such as authn_file and authz_user.
apache2_modules_authz_dbd
Provides authorization capabilities via SQL database so that authenticated users can be allowed or denied access to portions of the web site by group membership.
apache2_modules_cache_disk
Disk based storage module for the HTTP caching filter (similar to mem_cache in previous versions).
apache2_modules_lbmethod_byrequests
Request counting load balancer scheduler algorithm for proxy_balancer.
apache2_modules_lbmethod_bytraffic
Weighted traffic counting load balancer scheduler algorithm for proxy_balancer.
apache2_modules_lbmethod_bybusyness
Pending request counting load balancer scheduler algorithm for proxy_balancer.
apache2_modules_lbmethod_heartbeat
Heartbeat traffic counting load balancer scheduler algorithm for proxy_balancer.
apache2_modules_slotmem_shm
Slot-based shared memory provider.
apache2_modules_socache_shmcb
A shared object cache provider using a high-performance cyclic buffer inside a shared memory segment.
apache2_modules_unixd
Basic (required) security for Unix-family platforms.
apache2_modules_proxy_fcgi
FCGI support module for mod_proxy.
apache2_modules_proxy_wstunnel
Provides support for the tunnelling of web socket connections to a backend websockets server.
apache2_modules_ratelimit
Ratelimit module for transfer rate management
apache2_modules_remoteip
Remotip module for logging

Apache

Apache is a powerful web server which serves html/css/cgi/pl out of the box, and can serve other languages/frameworks via extensions.

The Apache Homepage says this of Apache:

The Apache HTTP Server Project is an effort to develop and maintain an open-source HTTP server for modern operating systems including UNIX and Windows NT. The goal of this project is to provide a secure, efficient and extensible server that provides HTTP services in sync with the current HTTP standards.

Install

USE Flags

Use flag Default Recommended Description
debug No No Enable extra debug codepaths, like asserts and extra output. If you want to get meaningful backtraces see http://www.gentoo.org/proj/en/qa/backtraces.xml.
doc No Add extra documentation (API, Javadoc, etc). It is recommended to enable per package instead of globally
ldap No Add LDAP support (Lightweight Directory Access Protocol).
selinux No No, unless selected by default.  !!internal use only!! Security Enhanced Linux support, this must be set by the selinux profile or breakage will occur
ssl Yes Add support for Secure Socket Layer connections.
static No  !!do not set this during bootstrap!! Causes binaries to be statically linked instead of dynamically.
threads No Add threads support for various packages. Usually pthreads.

If you want to enable any of the above use flags, create a file called /etc/portage/package.use/apache and add the options that you want to enable to it. For example:

/etc/portage/package.use/apache
www-servers/apache ssl threads

Emerge

After you have configured the USE flags that you want to build Apache with, emerge it:

# emerge apache

Configuration

System

Many packages have apache2 use flags. These use flags are often required for an application to be supported by Apache. Setting a system wide apache2 use flag is a good idea.

/etc/portage/make.conf: set system wide apache2 useflag
USE="...,apache2,..."

Package

Apache's configuration files are broken up and located in several spots.

  • /etc/conf.d/apache2
  • /etc/apache2/httpd.conf
  • /etc/apache2/modules.d/*
  • /etc/apache2/vhosts.d/*

conf.d controls the init script, adding things to it such as -D SECURITY & -D PHP5 will enable web application fire-walling & the php scripting language.

httpd.conf controls how the server behaves, at the bottom of the file it has directives to include configuration files ending in .conf in /etc/apache2/modules.d and /etc/apache2/vhosts.d

Service

To start apache immediately:

# rc-service apache2 start

To start apache upon boot:

# rc-update add apache2

mod_rewrite

What is mod_rewrite?

The Apache documentation describes mod_rewrite as:

The mod_rewrite module uses a rule-based rewriting engine, based on a PCRE regular-expression parser, to rewrite requested URLs on the fly. By default, mod_rewrite maps a URL to a filesystem path. However, it can also be used to redirect one URL to another URL, or to invoke an internal proxy fetch.

Setting it up

mod_rewrite has a reputation of being difficult to set up. mod_rewrite requires following symlinks & Order allow,deny (apache 2.2) or Require all granted (apache 2.4) is set. To test functionality of mod_rewrite we will need to make a few files.

Note

If you want to test this for web applications such as mediawiki adjust the path to /var/www/localhost/htdocs/mediawiki/.htaccess

/var/www/localhost/htdocs/.htaccess: enable the rewrite engine
RewriteEngine on 
RewriteRule ^test.html$ rewrite.html
/var/www/localhost/htdocs/test.html: set system wide apache2 useflag
rewrite is not working
/var/www/localhost/htdocs/rewrite.html: set system wide apache2 useflag
rewrite is working

Then point your browser to http://127.0.0.1/test.html. You should see that the text from rewrite.html has been loaded.