[v. reverse proxy and related configurations]

Reverse proxy and its related configuration

1. Reverse proxy

The proxy provided by the server is a reverse proxy

principle ： When a user requests resources from the server , He will First in Nginx, from Nginx Then request resources from the server , When you get the resources , The server will first send resources to Nginx On , Then from Nginx Send to the user , here Nginx It's the reverse proxy server .

2. Forward agency

The proxy provided by the user is a forward proxy （socket agent ,http Agent etc. ）

3. gateway

Forward proxy 、 The reverse proxy server is essentially the same as the gateway .

The gateway is the gateway to access the network , For example, a router in a home is equivalent to a gateway , I'm using my home phone , Tablet, etc , Accessing resources will be called to the gateway , In transmission out . A popular gateway is equivalent to the gate of a school , You want to go out , You have to go through the gate .

Gateway features ： transit .

User access to resources , All need to enter the gateway , When the request is sent to the server through the gateway , The server will send the information , To the gateway , Finally, it is passed to the user .

problem ： When a user requests more , When the flow is high , If the maximum bandwidth of the gateway is not large , There will be a blockage .

resolvent ： You can only increase the bandwidth of the proxy server .

4. Nginx The disadvantages of reverse proxy

because nginx Proxy bandwidth , Determines the network bandwidth of the user cluster , At higher io operation ,nginx Acting as a reverse agent , The effect is not obvious .

Solution ： When a user requests the server , Must go through nginx, But when the server returns data , Call the user directly , Not after nginx（DR Model ）

5. Reverse agent configuration

1. Jump to the extranet website

be used proxy_pass Keyword settings

proxy_pass There are two configuration methods

1. It can be the address of the agent , This address can be a host or a web address

2. You can configure it into a group of servers （ The following is a server ）

worker_processes  1;

events {
    
    worker_connections  1024;
}


http {
    
    include       mime.types;
    default_type  application/octet-stream;

    sendfile        on;

    keepalive_timeout  65;

    server {
    
        listen       80;
        server_name  localhost; 

        location / {
    
             proxy_pass   http://www.baidu.com;             // Only this place has changed 
            #root   html;
            #index  index.html index.htm;
        }

        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
    
            root   html;
        }

    }

}

Running results ：

2. Jump to the local server

Set up two virtual hosts ： Here is a ip:192.168.56.136, The other is 192.168.56.137

I use the bridging method , direct nat Methods and host only methods have been tried , But both virtual machines ping no .

Be careful ：

• When the agent arrives at the website , Virtual machine requirements Ping Only through the Internet can

• When proxy the local server , Two virtual machines need ping A generalist can .（ Which server do you want to proxy , You just need to be with someone ping through ）

Modify the network configuration command

vi /etc/sysconfig/network-scripts/ifcfg-ens33

CentOS7 Configuration situation ：(ip:192.168.56.136)

TYPE="Ethernet"
PROXY_METHOD="none"
BROWSER_ONLY="no"
BOOTPROTO="DHCP"
DEFROUTE="yes"
IPV4_FAILURE_FATAL="no"
IPV6INIT="yes"
IPV6_AUTOCONF="yes"
IPV6_DEFROUTE="yes"
IPV6_FAILURE_FATAL="no"
IPV6_ADDR_GEN_MODE="stable-privacy"
NAME="ens33"
UUID="b73ab354-05d7-4492-87df-d537a32120bd"
DEVICE="ens33"
ONBOOT="yes"
IPADDR=192.168.56.136
NETMASK=255.255.255.0
GETWAY=192.168.56.2
DNS1=8.8.8.8

Nginx Configuration situation ：（ip:192.168.56.137）

TYPE="Ethernet"
PROXY_METHOD="none"
BROWSER_ONLY="no"
BOOTPROTO="DHCP"
DEFROUTE="yes"
IPV4_FAILURE_FATAL="no"
IPV6INIT="yes"
IPV6_AUTOCONF="yes"
IPV6_DEFROUTE="yes"
IPV6_FAILURE_FATAL="no"
IPV6_ADDR_GEN_MODE="stable-privacy"
NAME="ens33"
UUID="b73ab354-05d7-4492-87df-d537a32120bd"
DEVICE="ens33"
ONBOOT="yes"
IPADDR=192.168.56.137
NETMASK=255.255.255.0
GETWAY=192.168.56.2
DNS=8.8.8.8
         

To configure centos7 Medium nginx.conf file The file has only been modified in one place

worker_processes  1;




events {
    
    worker_connections  1024;
}


http {
    
    include       mime.types;
    default_type  application/octet-stream;


    sendfile        on;

    keepalive_timeout  65;

    server {
    
        listen       80;
        server_name  localhost;


        location / {
    
            proxy_pass http://192.168.56.137;         // This is the only place that has changed 
            #root   html;
            #index  index.html index.htm;
        }

       
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
    
            root   html;
        }

    }

}

To configure nginx2 Medium nginx.conf file File not modified , Keep the default

worker_processes  1;


events {
    
    worker_connections  1024;
}

http {
    
    include       mime.types;
    default_type  application/octet-stream;


    sendfile        on;


    keepalive_timeout  65;


    server {
    
        listen       80;
        server_name  localhost;


        location / {
    
            
            root   html;
            index  index.html index.htm;
        }

        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
    
            root   html;
        }

      
    }


}

To distinguish between the default root Under the html, take 192.168.56.137 Below html Change the document to

<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
</head>
<body>
<body style="background-color: pink">
<h1>192.168.56.137</h1>
</body>
</html>

Running results ：（ By entering 192.168.56.136, Due to the proxy_pass He will jump to 192.168.56.137, Then show 137 Below html file ）

At present, it is only a proxy server , You can proxy to multiple servers