Downloading and Installing Nginx HTTP Server : Configure options

There are usually three steps when building an application from source the configuration, the compilation, and the installation. The configuration step allows you to select a number of options that will not be editable after the program is built, as it has a direct impact on the project binaries. Consequently, it is a very important stage that you need to follow carefully if you want to avoid surprises later, such as the lack of a specific module or files being located in a random folder.

The process consists of appending certain switches to the configure script that come with the source code. We will discover the three types of switches that you can activate; but let us first study the easiest way to proceed.

The easy way

If, for some reason, you do not want to bother with the configuration step, such as, for testing purposes or simply because you will be recompiling the application in the future, you may simply use the configure command with no switches. Execute the following three commands to build and install a working version of Nginx:

[[email protected] nginx-0.7.66]# ./configure

Running this command should initiate a long procedure of verifications to ensure that your system contains all the necessary components. If the configuration process fails, please make sure to check the prerequisites section again, as it is the most common cause of errors. For information about why the command failed, you may also refer to the objs/autoconf.err file, which provides a more detailed report.

[[email protected] nginx-0.7.66]# make

The make command will compile the application; this step should not cause any errors as long as the configuration went fine.

[[email protected] nginx-0.7.66]# make install

This last step will copy the compiled files as well as other resources to the installation directory, by default, /usr/local/nginx. You may need to be logged in as root to perform this operation depending on permissions granted to the /usr/local directory.

Again, if you build the application without configuring it, you take the risk to miss out on a lot of features, such as the optional modules and others that we are about to discover.

Path options

When running the configure command, you have the possibility to enable some switches that let you specify directory or file paths for a variety of elements. Please note that the options offered by the configuration switches may change according to the version you downloaded. The options listed below are valid with the stable version, release 0.7.66. If you use another version, run the configure --help command to list the available switches for your setup.

Using a switch typically consists of appending some text to the command line. For instance, using the --conf-path switch:

[[email protected] nginx-0.7.66]# ./configure --conf-path=/etc/nginx/nginx.conf


					  

Here is an exhaustive list of the configuration switches for configuring paths:

Switch	Usage	Default Value
--prefix=…	The base folder in which Nginx will be installed.	/usr/local/nginx. Note: If you configure other switches using relative paths, they will connect to the base folder. For example: Specifying --conf-path=conf/nginx.conf will result in your configuration file being found at /usr/local/nginx/conf/nginx.conf.
--sbin-path=…	The path where the nginx binary file should be installed.	<prefix>/sbin/nginx.
--conf-path=…	The path of the main configuration file.	<prefix>/conf/nginx.conf.
--error-log-path=…	The location of your error log. Error logs can be configured very accurately in the configuration files. This path only applies in case you do not specify any error logging directive in your configuration.	<prefix>/logs/error.log.
--pid-path=…	The path of the Nginx pid file. You can specify the pid file path in the configuration file; if it's not the case, the value you specify for this switch will be used.	<prefix>/logs/nginx.pid. Note: The pid file is a simple text file containing the process identifier. It is placed in a well-defined location so that other applications can easily find the pid of a running program.
--lock-path=…	The location of the lock file. Again, it can be specified in the configuration file, but if it isn't, this value will be used.	<prefix>/logs/nginx.lock. Note: The lock file allows other applications to determine whether or not the program is running. In the case of Nginx, it is used to make sure that the process is not started twice.
--with-perl_modules_path=…	Defines the path to the Perl modules. This switch must be defined if you want to include additional Perl modules.
--with-perl=…	Path to the Perl binary file; used for executing Perl scripts. This path must be set if you want to allow execution of Perl scripts.
--http-log-path=…	Defines the location of the access logs. This path is used only if the access log directive is unspecified in the configuration files.	<prefix>/logs/access.log.
--http-client-body-temp-path=…	Directory used for storing temporary files generated by client requests.	<prefix>/client_body_temp.
--http-proxy-temp-path=…	Location of the temporary files used by the proxy.	<prefix>/proxy_temp.
--http-fastcgi-temp-path=…	Location of the temporary files used by the HTTP FastCGI module.	<prefix>/fastcgi_temp.
--builddir=…	Location of the application build.

Prerequisites options

Prerequisites come in the form of libraries and binaries. You should by now have them all installed on your system. Yet, even though they are present on your system, there may be occasions where the configuration script cannot locate them. The reasons might be diverse, for example, if they were installed in nonstandard directories. In order to fix this problem, you are given the option to specify the path of prerequisites using the following switches. Miscellaneous prerequisite-related options are grouped together.

Compiler options
--with-cc=…	Specifies an alternate location for the C compiler.
--with-cpp=…	Specifies an alternate location for the C preprocessor.
--with-cc-opt=…	Defines additional options to be passed to the C compiler command line.
--with-ld-opt=…	Defines additional options to be passed to the C linker command line.
--with-cpu-opt=…	Specifies a different target processor architecture, among the following values: pentium, pentiumpro, pentium3, pentium4, athlon, opteron, sparc32, sparc64, and ppc64.
PCRE options
--without-pcre	Disables usage of the PCRE library. This setting is not recommended, as it will remove support for regular expressions, consequently disabling the Rewrite module.
--with-pcre	Forces usage of the PCRE library.
--with-pcre=…	Allows you to specify the path of the PCRE library source code.
--with-pcre-opt=…	Additional options for building the PCRE library.
MD5 options
--with-md5=…	Specifies the path to the MD5 library sources.
--with-md5-opt=…	Additional options for building the MD5 library.
--with-md5-asm	Uses assembler sources for the MD5 library.
SHA1 options
--with-sha1=…	Specifies the path to the SHA1 library sources.
--with-sha1-opt=…	Additional options for building the SHA1 library.
--with-sha1-asm	Uses assembler sources for the SHA1 library.
zlib options
--with-zlib=…	Specifies the path to the zlib library sources.
--with-zlib-opt=…	Additional options for building the zlib library.
--with-zlib-asm=…	Uses assembler optimizations for the following target architectures: pentium, pentiumpro.
OpenSSL options
--with-openssl=…	Specifies the path of the OpenSSL library sources.
--with-openssl-opt=…	Additional options for building the OpenSSL library.

Module options

Modules, need to be selected before compiling the application. Some are enabled by default and some need to be enabled manually, as you will see in the table below.

Modules enabled by default

The following switches allow you to disable modules that are enabled by default.

Modules enabled by default	Description
--without-http_charset_module	Disables the Charset module for re-encoding web pages.
--without-http_gzip_module	Disables the Gzip compression module.
--without-http_ssi_module	Disables the Server Side Include module.
--without-http_userid_module	Disables the User ID module providing user identification via cookies.
--without-http_access_module	Disables the Access module allowing access configuration for IP address ranges.
--without-http_auth_basic_module	Disables the Basic Authentication module.
--without-http_autoindex_module	Disables the Automatic Index module.
--without-http_geo_module	Disables the Geo module allowing you to define variables depending on IP address ranges.
--without-http_map_module	Disables the Map module that allows you to declare map blocks.
--without-http_referer_module	Disables the Referer control module.
--without-http_rewrite_module	Disables the Rewrite module.
--without-http_proxy_module	Disables the Proxy module for transferring requests to other servers.
--without-http_fastcgi_module	Disables the FastCGI module for interacting with a FastCGI process.
--without-http_memcached_module	Disables the Memcached module for interacting with the memcache daemon.
--without-http_limit_zone_module	Disables the Limit Zone module for restricting resource usage according to defined zones.
--without-http_limit_req_module	Disables the Limit Requests module allowing you to limit the amount of requests per user.
--without-http_empty_gif_module	Disables the Empty Gif module for serving a blank GIF image from memory.
--without-http_browser_module	Disables the Browser module for interpreting the User Agent string.
--without-http_upstream_ip_hash_module	Disables the Upstream module for configuring load-balanced architectures.

Modules disabled by default

The following switches allow you to enable modules that are disabled by default.

Modules disabled by default	Description
--with-http_ssl_module	Enables the SSL module for serving pages using HTTPS.
--with-http_realip_module	Enables the Real IP module for reading the real IP address from the request header data.
--with-http_addition_module	Enables the Addition module which lets you append or prepend data to the response body.
--with-http_xslt_module	Enables the XSLT module for applying XSL transformations to XML documents. Note: You will need to install the libxml2 and libxslt libraries on your system if you wish to compile these modules.
--with-http_image_filter_module	Enables the Image Filter module that lets you apply modification to images. Note: You will need to install the libgd library on your system if you wish to compile this module.
--with-http_geoip_module	Enables the GeoIP module for achieving geographic localization using MaxMind's GeoIP binary database. Note: You will need to install the libgeoip library on your system if you wish to compile this module.
--with-http_sub_module	Enables the Substitution module for replacing text in web pages.
--with-http_dav_module	Enables the WebDAV module (Distributed Authoring and Versioning via Web).
--with-http_flv_module	Enables the FLV module for special handling of .flv (flash video) files.
--with-http_gzip_static_module	Enables the Gzip Static module for sending pre-compressed files.
--with-http_random_index_module	Enables the Random Index module for picking a random file as the directory index.
--with-http_secure_link_module	Enables the Secure Link module to check the presence of a keyword in the URL.
--with-http_stub_status_module	Enables the Stub Status module, which generates a server statistics and information page.
--with-google_perftools_module	Enables the Google Performance Tools module.

Miscellaneous options

Other options are available in the configuration script, for example, regarding the mail server proxy feature or event management.

Mail server proxy options
--with-mail	Enables mail server proxy module. Supports POP3, IMAP4, SMTP. It is disabled by default.
--with-mail_ssl_module	Enables SSL support for the mail server proxy. It is disabled by default.
--without-mail_pop3_module	Disables the POP3 module for the mail server proxy. It is enabled by default when the mail server proxy module is enabled.
--without-mail_imap_module	Disables the IMAP4 module for the mail server proxy. It is enabled by default when the mail server proxy module is enabled.
--without-mail_smtp_module	Disables the SMTP module for the mail server proxy. It is enabled by default when the mail server proxy module is enabled.

Event management: Allows you to select the event notification system for the Nginx sequencer. For advanced users only.
--with-rtsig_module	Enables the rtsig module to use rtsig as event notification mechanism.
--with-select_module	Enables the select module to use select as event notification mechanism. By default, this module is enabled unless a better method is found on the system kqueue, epoll, rtsig, or poll.
--without-select_module	Disables the select module.
--with-poll_module	Enables the poll module to use poll as event notification mechanism. By default, this module is enabled if available, unless a better method is found on the system kqueue, epoll, or rtsig.
--without-poll_module	Disables the poll module.
User and group options
--user=…	Default user account for starting the Nginx worker processes. This setting is used only if you omit to specify the user directive in the configuration file.
--group=…	Default user group for starting the Nginx worker processes. This setting is used only if you omit to specify the group directive in the configuration file.

Other options
--with-ipv6	Enables IPv6 support.
--without-http	Disables the HTTP server.
--without-http-cache	Disables HTTP caching features.
--add-module=PATH	Adds a third-party module to the compile process by specifying its path. This switch can be repeated indefinitely if you wish to compile multiple modules.
--with-debug	Enables additional debugging information to be logged.

Configuration examples

Here are a few examples of configuration commands that may be used for various cases. In these examples, the path switches were omitted as they are specific to each system and leaving the default values may simply function correctly.

Be aware that these configurations do not include additional third-party modules.

About the prefix switch

During the configuration, you should take particular care over the --prefix switch. Many of the future configuration directives will be based on the path you selected at this point. While it is not a definitive problem since absolute paths can still be employed, you should know that the prefix cannot be changed once the binaries have been compiled.

There is also another issue that you may run into if you plan to keep up with the times and update Nginx as new versions are released. The default prefix (if you do not override the setting by using the --prefix switch) is /usr/local/nginx a path that does not include the version number. Consequently, when you upgrade Nginx, if you do not specify a different prefix, the new install files will override the previous ones, which among other problems, could potentially erase your configuration files and running binaries.

It is thus recommended to use a different prefix for each version you will be using:

./configure --prefix=/usr/local/nginx-0.7.66

Additionally, to make future changes simpler, you may create a symbolic link /usr/local/nginx pointing to /usr/local/nginx-0.7.66. Once you upgrade, you can update the link to make it point to /usr/local/nginx-newer.version. This will (for example) allow the init script to always make use of the latest installed version of Nginx.

Regular HTTP and HTTPS servers

The first example describes a situation where the most important features and modules for serving HTTP and HTTPS content are enabled, and the mail-related options are disabled.

./configure --user=www-data --group=www-data --with-http_ssl_module --with-http_realip_module


					  

As you can see, the command is rather simple and most switches were left out. The reason being: the default configuration is rather efficient and most of the important modules are enabled. You will only need to include the http_ssl module for serving HTTPS content, and optionally, the "real IP" module for retrieving your visitors' IP addresses in case you are running Nginx as backend server.

All modules enabled

The next situation: the whole package. All modules are enabled and it is up to you whether you want to use them or not at runtime.

./configure --user=www-data --group=www-data --with-http_ssl_module --with-http_realip_module --with-
http_addition_module --with-http_xslt_module --with-http_image_filter_module --with-http_geoip_module --with-
http_sub_module --with-http_dav_module --with-http_flv_module --with-http_gzip_static_module --with-
http_random_index_module --with-http_secure_link_module --with-http_stub_status_module


					  

This configuration opens up a wide range of possible configuration options.

With this setup, all optional modules are enabled, thus requiring additional libraries to be installed libgeoip for the Geo IP module, libgd for the Image Filter module, libxml2, and libxslt for the XSLT module. You may install those prerequisites using your system package manager such as running yum install libxml2 or apt-get install libxml2.

Mail server proxy

This last build configuration is somewhat special as it is dedicated to enabling mail server proxy features a darker side of Nginx. The related features and modules are all enabled.

./configure --user=www-data --group=www-data --with-mail --with-mail_ssl_module
    

					  

If you wish to completely disable the HTTP serving features and only dedicate Nginx to mail proxying, you can add the --without-http switch.

Note that in the commands listed above, the user and group used for running the Nginx worker processes will be www-data which implies that this user and group must exist on your system.

Build configuration issues

In some cases, the configure command may fail after a long list of checks, you may receive a few error messages on your terminal. In most (if not all) cases, these errors are related to missing prerequisites or unspecified paths.

In such cases, proceed with the following verifications carefully to make sure you have all it takes to compile the application, and optionally consult the objs/autoconf.err file for more details about the compilation problem. This file is generated during the configure process and will tell you exactly where the process failed.

Make sure you installed the prerequisites

There are basically four main prerequisites: GCC, PCRE, zlib, and OpenSSL. The last three are libraries that must be installed in two packages: the library itself and its development sources. Make sure you have installed both for each of them. Note that other prerequisites such as LibXML2 or LibXSLT might be required for enabling extra modules, for example, in the case of the HTTP XSLT module.

If you are positive that all prerequisites were installed correctly, perhaps the issue comes from the fact that the configure script is unable to locate the prerequisite files. In that case, make sure that you include the switches related to file paths, as described earlier.

For example, the following switch allows you to specify the location of the OpenSSL library files:

./configure [...] --with-openssl=/usr/lib64

The OpenSSL library file will be looked for in the specified folder.

Directories exist and are writable

Always remember to check the obvious; everyone makes even the simplest of mistakes sooner or later. Make sure the directory you placed the Nginx files in has read and write permissions for the user running the configuration and compilation scripts. Also ensure that all paths specified in the configure script switches are existing, valid paths.

Eventually, when all your issues are solved, you should be seeing a configuration summary more or less similar to the image below:

Compiling and installing

The configuration process is of utmost importance it generates a makefile for the application depending on the selected switches and performs a long list of requirement checks on your system. Once the configure script is successfully executed, you can proceed with compiling Nginx.

Compiling the project equates to executing the make command in the project source directory:

[[email protected] nginx-0.7.66]$ make

A successful build should result in a final message appearing: make[1]: leaving directory followed by the project source path.

Again, problems might occur at compile time. Most of these problems can originate in missing prerequisites or invalid paths specified. If this occurs, run the configure script again and triple-check the switches and all the prerequisite options. It may also occur that you downloaded a too recent version of the prerequisites that might not be backwards compatible. In such cases, the best option is to visit the official website of the missing component and download an older version.

If the compilation process was successful, you are ready for the next step: installing the application.

[[email protected] nginx-0.7.66]$ make install

The make install command executes the install section of the makefile. In other words, it performs a few simple operations such as copying binaries and configuration files to the specified install folder. It also creates directories for storing log and HTML files if these do not already exist. The make install step is not generally a source of problems, unless your system encounters some exceptional error such as a lack of storage space or memory.

You might require root privileges for installing the application in the /usr/local/ folder, depending on the folder permissions.