Comprehensive Nginx Tutorial: Installation, Configuration, Reverse Proxy, Load Balancing, and High Availability

This article presents a complete walkthrough of Nginx, starting with an overview of its high performance HTTP and reverse‑proxy capabilities and listing major users such as Baidu, Tencent, and Alibaba.

Installation : It demonstrates preparing a CentOS 6.10 VM, installing required packages, downloading Nginx 1.18.0, extracting, configuring, compiling, and installing to /usr/local/nginx. Example commands include:

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

# wget http://nginx.org/download/nginx-1.18.0.tar.gz

# tar -zxvf nginx-1.18.0.tar.gz

# cd nginx-1.18.0 && ./configure && make && make install

After installation, the service can be started with /usr/local/nginx/sbin/nginx and stopped with /usr/local/nginx/sbin/nginx -s quit. Firewall rules are opened using iptables to allow port 80.

Reverse Proxy : The guide shows how to configure location / blocks to proxy requests to Tomcat instances, including necessary proxy_set_header directives to preserve client IP and host information.

Load Balancing : An upstream block named myserver is defined with two backend servers (ports 8080 and 8081). The server block proxies traffic to this upstream, demonstrating round‑robin distribution and explaining alternative strategies such as weight, ip_hash, and fair.

Static/Dynamic Separation : By adding a location /www/ block with root /data/, static files are served directly by Nginx while dynamic content continues to be handled by Tomcat.

High Availability : The article introduces keepalived for VRRP‑based failover. It provides a sample /etc/keepalived/keepalived.conf configuration, a health‑check script /etc/keepalived/nginx_check.sh, and steps to start the keepalived service, ensuring a virtual IP remains reachable if the primary Nginx node fails.

Configuration Details : It explains the global, events, http, server, and location blocks, covering directives such as worker_processes, worker_connections, sendfile, gzip, and SSL settings. The syntax and wildcard behavior of the location directive (=, ~, ~*, ^~) are also described.

Nginx Architecture : The master‑worker model is illustrated, noting that the master process manages workers and configuration reloads, while workers handle connections using the epoll event model. Calculations for maximum concurrent connections are provided for both static serving and reverse‑proxy scenarios.

Overall, the tutorial equips readers with practical commands, configuration examples, and architectural insights needed to deploy, tune, and maintain a robust Nginx infrastructure.