1. Basic concepts of Nginx reverse proxy

Nginx is a high-performance HTTP and reverse proxy server that can be used as a reverse proxy server to forward requests to different back-end servers. Configuring Nginx reverse proxy on CentOS can help us to implement features such as load balancing, security enhancement and content caching. To configure Nginx reverse proxy, you first need to install Nginx and understand some basic concepts.

2. Installing and configuring Nginx on CentOS

First, we need to install the Nginx package. On CentOS, you can use the yum package manager to install Nginx:
“`
sudo yum install nginx
“`
Once the installation is complete, you can start Nginx and set up a boot self-start:
“`
sudo systemctl start nginx
sudo systemctl enable nginx
“`
Next, we need to edit the Nginx configuration file for reverse proxy configuration. Open the Nginx configuration file (usually /etc/nginx/nginx.conf), find the server section, and add the reverse proxy configuration:
“`
server {
listen 80.
server_name example.com.

location / {
proxy_pass http://backend_server.
proxy_set_header Host $host.
proxy_set_header X-Real-IP $remote_addr.
}
}
“`
In the above configuration, we are forwarding all requests from example.com to the backend server backend_server.Once the configuration is complete, reload the Nginx configuration file to make it take effect:
“`
sudo nginx -s reload
“`

3. Load balancing using Nginx reverse proxy

Nginx reverse proxy also enables load balancing to improve the performance and reliability of back-end servers. In the Nginx configuration file, you can use the upstream configuration item to specify multiple back-end servers and use proxy_pass in the location configuration item to implement load balancing:
“`
upstream backend_servers {
server backend1.example.com;
server backend2.example.com;
}

server {
listen 80.
server_name example.com.

location / {
proxy_pass http://backend_servers.
proxy_set_header Host $host.
proxy_set_header X-Real-IP $remote_addr.
}
}
“`
In the configuration example above, we specified two backend servers and used proxy_pass for load balancing.

With the above configuration, we can successfully configure and use Nginx reverse proxy on CentOS to realize the functions of forwarding requests, load balancing, etc., and improve the performance and reliability of the server. I hope the above can help you better understand and use Nginx reverse proxy.