Introduction

nginx pronounced as "engine x" is an HTTP and reverse proxy server, as well as a mail proxy server.

nginx is an opensource web server which uses epoll mechanism to serve clients as opposed to Apache which uses a thread based model which delegates the requests to an instance in the thread pool. nginx is being used more over Apache because of its speed. nginx has over 13% market share and increasing continuously.

Why compile from source

Compiling from the source code is useful when:

1. Upgrading to the latest version right after the release.
2. Fixing security vulnerabilities
3. Fixing known bugs which has been impacting your service
4. Modifying defaults like the server name
5. Applying patches with fixing known bugs
6. Software repositories are not upgraded with the latest version because of the dependency hierarchy

Its painful because:

1. You need to keep up to date with software versions
2. Your server software might depend on older versions in the dependency tree

Modules and 3rd Party Modules

nginx has many modules which add features on top of existing VPS. Some of the famous 3rd party modules are:

• SPDY was included in nginx 1.5.0 (earlier was provided as a patch)
• google pagespeed(source) speeds up your site and reduces page load time by automatically applying web performance best practices to pages and associated assets (CSS, JavaScript, images) without requiring you to modify your existing content or workflow
• ModSecurity is an open source web application firewall to reduce known attacks on application servers. *TCP Proxy allows nginx to proxy through tcp server instead of the default socket mode.

Setup your VPS

Create a new VPS or choose an existing one

Create a new VPS with your domain name. We will be using 'example.com' as the domain or you can use the server IP instead of the hostname.

Setting Up Pre-requisites to Compile from Source

Securely Login into your VPS

You can login into the VPS with your password for your host.

ssh root@example.com

Install dependencies for nginx

We have few pre-requisites to be installed to compile which include development libraries along with source code compilers.

yum -y install gcc gcc-c++ make zlib-devel pcre-devel openssl-devel

Lets first create a directory to store our source code:

mkdir -p src && cd src

Compiling from Source

Downloading the source code

Lets get the current nginx version number from http://nginx.org/en/download.html

Run the following commands to download the source.

nginxVersion="1.5.5"
wget http://nginx.org/download/nginx-$nginxVersion.tar.gz
tar -xzf nginx-$nginxVersion.tar.gz 
ln -sf nginx-$nginxVersion nginx

Preparing the nginx source

We first want to prepare nginx with necessary basic options.

For a full list of options you can look at ./configure --help

Options for basic file path names

These options are the basic variables which we override to use default system paths at /etc/ to ensure it works simliar when installed via rpm. The user and group option are used to run the nginx worker processes in non-privileged.

--user
--group
--prefix
--sbin-path
--conf-path
--pid-path
--lock-path
--error-log-path
--http-log-path

Other options

• --with-http_gzip_static_module option enables nginx to use gzip (Before serving a file from disk to a gzip-enabled client, this module will look for a precompressed file in the same location that ends in ".gz". The purpose is to avoid compressing the same file each time it is requested.).[recommended for reducing size of information sent]

• --with-http_stub_status_module option enables other plugins over nginx to allow us to get the status (This module provides the ability to get some status from nginx.). [recommended for getting stats]

• --with-http_ssl_module - required if you want to run a HTTPS server. See How To Create a SSL Certificate on nginx for CentOS 6

• --with-pcre option enables to match routes via Regular Expression Matching when defining routes. [recommended, you will find more use of this once you start adding and matching routes]

• --with-file-aio - enables asynchronous I/O, better than the default send file option (recommended if you are allowing users to download static files)

• --with-http_realip_module is used for getting the IP of the client when behind a load balancer. This is useful when serving content behind CloudFlare like services.

• --without-http_scgi_module - Disable SCGI module (normally used when running CGI scripts)

• --without-http_uwsgi_module - Disable UWSGI module (normally used when running CGI scripts)

• --without-http_fastcgi_module - Disable FastCGI module (normally used when running CGI scripts)

Our configuration options

cd nginx

./configure \
--user=nginx                          \
--group=nginx                         \
--prefix=/etc/nginx                   \
--sbin-path=/usr/sbin/nginx           \
--conf-path=/etc/nginx/nginx.conf     \
--pid-path=/var/run/nginx.pid         \
--lock-path=/var/run/nginx.lock       \
--error-log-path=/var/log/nginx/error.log \
--http-log-path=/var/log/nginx/access.log \
--with-http_gzip_static_module        \
--with-http_stub_status_module        \
--with-http_ssl_module                \
--with-pcre                           \
--with-file-aio                       \
--with-http_realip_module             \
--without-http_scgi_module            \
--without-http_uwsgi_module           \
--without-http_fastcgi_module

Compiling the nginx source

Once we are able to configure the source which even checks for additional requirements like the compiler(gcc, g++) which we installed in the pre-requisites step:

 make
 make install

Running the VPS

1. Add the user nginx to the system. This is a one time command:

   useradd -r nginx
   

2. We need to setup the file /etc/init.d/nginx to run when system starts:

   #!/bin/sh
   #
   # nginx - this script starts and stops the nginx daemin
   #
   # chkconfig:   - 85 15
   # description:  Nginx is an HTTP(S) server, HTTP(S) reverse \
   #               proxy and IMAP/POP3 proxy server
   # processname: nginx
   # config:      /etc/nginx/nginx.conf
   # pidfile:     /var/run/nginx.pid
   # user:        nginx
   
   # Source function library.
   . /etc/rc.d/init.d/functions
   
   # Source networking configuration.
   . /etc/sysconfig/network
   
   # Check that networking is up.
   [ "$NETWORKING" = "no" ] && exit 0
   
   nginx="/usr/sbin/nginx"
   prog=$(basename $nginx)
   
   NGINX_CONF_FILE="/etc/nginx/nginx.conf"
   
   lockfile=/var/run/nginx.lock
   
   start() {
       [ -x $nginx ] || exit 5
       [ -f $NGINX_CONF_FILE ] || exit 6
       echo -n $"Starting $prog: "
       daemon $nginx -c $NGINX_CONF_FILE
       retval=$?
       echo
       [ $retval -eq 0 ] && touch $lockfile
       return $retval
   }
   
   stop() {
       echo -n $"Stopping $prog: "
       killproc $prog -QUIT
       retval=$?
       echo
       [ $retval -eq 0 ] && rm -f $lockfile
       return $retval
   }
   
   restart() {
       configtest || return $?
       stop
       start
   }
   
   reload() {
       configtest || return $?
       echo -n $"Reloading $prog: "
       killproc $nginx -HUP
       RETVAL=$?
       echo
   }
   
   force_reload() {
       restart
   }
   
   configtest() {
     $nginx -t -c $NGINX_CONF_FILE
   }
   
   rh_status() {
       status $prog
   }
   
   rh_status_q() {
       rh_status >/dev/null 2>&1
   }
   
   case "$1" in
       start)
           rh_status_q && exit 0
           $1
           ;;
       stop)
           rh_status_q || exit 0
           $1
           ;;
       restart|configtest)
           $1
           ;;
       reload)
           rh_status_q || exit 7
           $1
           ;;
       force-reload)
           force_reload
           ;;
       status)
           rh_status
           ;;
       condrestart|try-restart)
           rh_status_q || exit 0
               ;;
       *)
           echo $"Usage: $0 {start|stop|status|restart|condrestart|try-restart|reload|force-reload|configtest}"
           exit 2
   esac
   

   Optionally, you can obtain the source from:

   wget -O /etc/init.d/nginx https://gist.github.com/sairam/5892520/raw/b8195a71e944d46271c8a49f2717f70bcd04bf1a/etc-init.d-nginx
   

   This file should be made executable so that we can use it via 'service nginx ':

   chmod +x /etc/init.d/nginx
   

3. Set the service to start whenever the system boots:

   chkconfig --add nginx
   chkconfig --level 345 nginx on
   

4. Configure /etc/nginx/nginx.conf to set types_hash_bucket_size and server_names_hash_bucket_size which needs to be increased.

   http {
       include       mime.types;
       default_type  application/octet-stream;
       # add the below 2 lines under http around line 20
       types_hash_bucket_size 64;
       server_names_hash_bucket_size 128;
   

5. Start the server. This will start the VPS on port 80.

   service nginx start
   

Setup Complete

Visit example.com or your IP address in the browser. You will see:

Welcome to nginx!

Congratulations! Your brand new nginx server is up.

Maintenance

Restart nginx server when nginx binary is modified:
service nginx restart

Reload nginx when nginx.conf is modified:
service nginx reload

Configuring nginx Web Server

Upgrading to the Latest Version

Let's get the current nginx version from http://nginx.org/en/download.html

Run the following commands to download the source.

ssh root@example.com
cd ~/src/
nginxVersion="1.5.5" # set the value here from nginx website
wget http://nginx.org/download/nginx-$nginxVersion.tar.gz
tar -xzf nginx-$nginxVersion.tar.gz
rm nginx # removes the soft link
ln -sf nginx-$nginxVersion nginx

cd nginx

./configure \
--user=nginx                          \
--group=nginx                         \
--prefix=/etc/nginx                   \
--sbin-path=/usr/sbin/nginx           \
--conf-path=/etc/nginx/nginx.conf     \
--pid-path=/var/run/nginx.pid         \
--lock-path=/var/run/nginx.lock       \
--error-log-path=/var/log/nginx/error.log \
--http-log-path=/var/log/nginx/access.log \
--with-http_gzip_static_module        \
--with-http_stub_status_module        \
--with-http_ssl_module                \
--with-pcre                           \
--with-file-aio                       \
--with-http_realip_module             \
--without-http_scgi_module            \
--without-http_uwsgi_module           \
--without-http_fastcgi_module

make
make install

service nginx restart

More Resources on nginx

Resources about nginx on DigitalOcean