Questions tagged [apache2]

Apache (HTTP Server) /əˈpætʃiː/ is a modular cross-platform web server software with a large variety of features(called modules) including SSL, compression, log, proxy and server-side programming language interfaces like Perl, Python, Tcl, and PHP.

The Apache HTTP Server, commonly referred to as Apache ( /əˈpætʃiː/), is web server software notable for playing a key role in the initial growth of the World Wide Web. In 2009 it became the first web server software to surpass the 100 million website milestone.
Apache was the first viable alternative to the Netscape Communications Corporation web server (currently known as Oracle iPlanet Web Server), and has since evolved to rival other web servers in terms of functionality and performance. Typically Apache is run on a Unix-like operating system.

Apache is developed and maintained by an open community of developers under the auspices of the Apache Software Foundation. The application is available for a wide variety of operating systems, including , GNU, FreeBSD, , , Novell NetWare, AmigaOS, Mac OS X, Microsoft , OS/2, TPF, and eComStation. Released under the Apache License, Apache is characterized as open-source software.

Apache supports a variety of features, many implemented as compiled modules which extend the core functionality. These can range from server-side programming language support to authentication schemes. Some common language interfaces support , , , and . Popular authentication modules include mod_access, mod_auth, mod_digest, and mod_auth_digest, the successor to mod_digest. A sample of other features include SSL and TLS support (mod_ssl), a proxy module (mod_proxy), a URL rewriter (also known as a rewrite engine, implemented under mod_rewrite), custom log files (mod_log_config), and filtering support (mod_include and mod_ext_filter).
Popular compression methods on Apache include the external extension module, mod_gzip, implemented to help with reduction of the size (weight) of web pages served over HTTP. ModSecurity is an open source intrusion detection and prevention engine for web applications. Apache logs can be analyzed through a web browser using free scripts such as AWStats/W3Perl or Visitors.

Virtual Hosting allows one Apache installation to serve many different actual websites. For example, one machine with one Apache installation could simultaneously serve www.example.com, www.test.com, test47.test-server.test.com, etc.
Apache features configurable error messages, -based authentication databases, and content negotiation. It is also supported by several graphical user interfaces (GUIs). It supports password authentication and digital certificate authentication. Apache has a built in search engine and an authorizing tool and supports .

Although the main design goal of Apache is not to be the "fastest" web server, Apache does have performance comparable to other "high-performance" web servers. Instead of implementing a single architecture, Apache provides a variety of MultiProcessing Modules (MPMs) which allow Apache to run in a process-based, hybrid (process and thread) or event-hybrid mode, to better match the demands of each particular infrastructure. This implies that the choice of correct MPM and the correct configuration is important. Where compromises in performance need to be made, the design of Apache is to reduce latency and increase throughput, relative to simply handling more requests, thus ensuring consistent and reliable processing of requests within reasonable time-frames.

The Apache version considered by the Apache Foundation as providing high-performances is the multi-threaded version which mixes the use of several processes and several threads per process.

Unless you are asking about how to write Apache modules, questions with this tag probably belong on serverfault.com rather than stackoverflow.com.

Reference

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Need to allow encoded slashes on Apache

I'm currently trying to place a URL within a URL. For example: http://example.com/url/http%3A%2F%2Fwww.url2.com I'm aware that I have to encode the URL, which I have done, but now I am getting a 404 error back from the server rather than my app. I…
tommizzle
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Is it possible to put binary image data into html markup and then get the image displayed as usual in any browser?

It's an important security issue and I'm sure this should be possible. A simple example: You run a community portal. Users are registered and upload their pictures. Your application gives security rules whenever a picture is allowed to be displayed.…
Joern Akkermann
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How to enable loglevel debug on Apache2 server

My error.log contains: Request exceeded the limit of 10 internal redirects due to probable configuration error. Use 'LimitInternalRecursion' to increase the limit if necessary. Use 'LogLevel debug' to get a backtrace. I replaced loglevel on apache…
Tiger
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Is there a practical HTTP Header length limit?

I have a web application that adds contextual information to XmlHttpRequest objects using the setRequestHeader API. I am using a custom header name (e.g. X-Foo) and a JSON structured value. It isn't part of the URL QueryString or POST body because…
Kevin Hakanson
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Apache 2.4 configuration for ssl not working

Apache Server 2.4 with mod_jk 1.3.7 not working for ssl (https) Error 1: The Apache service named reported the following error: SSLSessionCache: 'shmcb' session cache not supported (known names: ). Maybe you need to load the appropriate socache…
Meuk Light
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Windows could not start the Apache2 on Local Computer - problem

During the installation of Apache2 I got the following message into cmd window: Installing the Apache2.2 service The Apache2.2 service is successfully installed. Testing httpd.conf.... Errors reported here must be corrected before the service…
vaske
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Best way to rotate Apache log files

I've got an Apache server that has one access log file that is topping 600MB. This makes it really hard to search the file or parse it. What software or modules for Apache are available that will make a daily copy of my access file to make it more…
Scott Gottreu
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Authorization header missing in django rest_framework, is apache to blame?

I've managed to extend TokenAuthentication and I have a working model when using the request session to store my tokens, however when I attempt to pass Authorization as a header parameter as described here, I noticed that my Responses come back…
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Vagrant/VirtualBox/Apache2 Strange Cache Behaviour

I'm using Vagrant to run an Ubuntu powered VirtualBox with Apache2. The webserver, among others, serves static files from my /vagrant directory. This works well most of the time. But when I change an image on my shared folder and reload the website,…
Philipp Spiess
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How to determine if OpenSSL and mod_ssl are installed on Apache2

Does anyone know the command to determine if OpenSSL and mod_ssl are installed on Apache2?
Fiona
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multiple django sites with apache & mod_wsgi

I want to host several sites with under the same server which uses Debian 5, say I have site1, site2 and site3, and assume my ip is 155.55.55.1: site1: 155.55.55.1:80 , script at /opt/django/site1/ site2: 155.55.55.1:8080, script at…
Hellnar
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Setup mod_proxy on apache http server

I wanted to reverse proxy a web service from my tomcat server using apache web server. I have modified the httpd.conf LoadModule proxy_module modules/mod_proxy.so AllowOverride none Require all denied ProxyPass …
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PHP errors NOT being displayed in the browser [Ubuntu 10.10]

I'm new to PHP and the whole LAMP stack but I've managed to get it up and running on my Ubuntu 10.10 system. Everything seems to be working with the exception of error reposting in the browser which I just can't seem to get working (and which I…
raven-king
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How can I prevent tons of apache processes spawning when I start apache and proceeding to kill my machine?

I have a highly trafficked application on one debian machine and apache has started acting strange. Every time I start apache, tons of apache processes are spawned, the app doesn't load at all, and very quickly the whole machine freezes and must be…
Adam Gries
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Creating a symbolic link in Sites directory

I have a file in my ~/Sites directory that works fine when I browse to it through coderama.local/~coderama/index2.php Now I want to get tricky and move my index2.php file to somewhere else on my system, so I do this by creating a symbolic link.…
Coderama
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