Recently, I've been very interested in the topic of reverse proxies returning different IPs. When we browse the web or access a server, we sometimes encounter situations where we need to use a reverse proxy to return different IPs. This not only protects the real IP address of the server, but also enables load balancing and access control. In this article, I will share with you some knowledge and tips about reverse proxy returning different IPs.

What is a reverse proxy?

First, let's understand what a reverse proxy is. A Reverse Proxy is a proxy server that receives requests from clients and then forwards those requests to a target server. When the target server receives the request, it sends the response to the proxy server, which in turn forwards the response to the client. In this way, the client does not communicate directly with the target server, but realizes the function of accessing the target server through the proxy server.

Why do I need a reverse proxy to return different IPs?

In practical applications, sometimes we need to use the function of reverse proxy to return different IPs. This may be because we want to hide the real server IP address to avoid being maliciously attacked; or it may be to achieve load balancing, so that different requests are distributed to different servers; or it may be to achieve access control, restricting the access rights of specific IP.

How to implement a reverse proxy to return different IPs?

Now, let's see how to realize the function of reverse proxy returning different IPs. In practice, we can use some mature reverse proxy software, such as Nginx, Apache HTTP Server and so on. All of these software provide rich configuration options that can help us realize the need to return different IPs. Below, I will list some sample code to demonstrate how to realize the function of reverse proxy returning different IPs in Nginx.

Sample Code I: Load Balancing

upstream backend {
server 192.168.1.1; server 192.168.1.1
upstream backend { server 192.168.1.1; server 192.168.1.1; upstream backend { server 192.168.1.1; upstream backend
server 192.168.1.1; server 192.168.1.2; server 192.168.1.2; server 192.168.1.3; upstream backend {
}

server {
location / {
proxy_pass http://backend; }
}
}

In this sample code, we define a load-balanced group called backend that contains the IP addresses of three servers. When a client sends a request, Nginx distributes the request to one of these three servers according to the load balancing algorithm.

Sample Code II: Access Control

geo $limited_access {
default 0;
192.168.1.0/24 1;
}

server {
if ($limited_access) {
if ($limited_access) {
return 403; }
}
proxy_pass http://backend;
}
}

In this sample code, we define a variable named limited_access that determines whether access is available based on the client's IP address. If the client's IP address is within the specified network segment, a 403 error is returned, otherwise the request is forwarded to the backend.

summarize

Through the introduction of this article, I believe you have a deeper understanding of the topic of reverse proxy return different IP. In practice, the reverse proxy can not only help us hide the real server IP address, but also to achieve load balancing and access control and other functions. I hope that this article can help you, but also hope that you can continue to summarize the experience and improve the technical level in practice.