Nginx load balancing configuration

　　Rotation training: Each request is assigned to different back-end servers one by one in chronological order. If the back-end server is down down, it can be automatically eliminated.

[[emailprotected] ~]# yum -y install nginx

[[email Protected] ~]# vim /etc/nginx/nginx.conf< /span>

#### Modify nginx.conf to default to rotation ####



‘‘‘

# 1. Upstream is written by itself and must be placed outside the server

upstream myservers {

 server 192.168.56.14:81;

 server 192.168.56.14:82;

}



# 2. The server actually already has one by default, you only need to modify the configuration in the location and specify the forwarding proxy.

server {

 location / {

 proxy_pass http://myservers;

}

}

‘‘‘

[[email protected]-node4 nginx]# systemctl start nginx < /span>

1, poll (Default)

Each request is allocated to different back-end servers one by one in chronological order, if the back-end The server is down and can be automatically removed.

upstream backserver {

 server 192.168.0.14;

 server 192.168.0.15;

}

2, weight weight< /span>

Specify the polling probability. The weight is proportional to the access ratio. It is used for the performance of the back-end server. All the situation.

upstream backserver {

 server 192.168.0.14 weight=3;

 server 192.168.0.15 weight=7;

}

3, IP_hash (IP Binding)

There is a problem with the above method, that is, in the load balancing system, if the user is in a certain Log in to the server, then when the user requests the second time, because we are a load balancing system, will be relocated to the server cluster every time a request is made If a user who has logged in to a certain server relocates to another server, his login information will be lost, which is obviously inappropriate. We can use the ip_hash instruction to solve this problem. If the customer has already visited a certain server, when the user visits again, the request will pass the hash algorithm , Automatically locate the server. Each request is allocated according to the hash result of the access ip, so that each visitor has a fixed access to a back-end server, which can solve the session problem.

upstream backserver {

 ip_hash;

 server 192.168.0.14:88;

 server 192.168.0.15:80;

}

4. fair (section Three-party plug-in)

The request is allocated according to the response time of the back-end server, and the short response time is given priority.

upstream backserver {

 server server1;

 server server2;

 fair;

}

5. url_hash (section Three-party plug-in)

According to the hash result of the access URL, the request is allocated, so that each URL is directed to the same one The back-end server is more effective when the back-end server is a cache.

upstream backserver {

 server squid1:3128;

 server squid2:3128;

 hash $request_uri;

 hash_method crc32;

}

1) Use to build the first nginx service

[[email protected]-node4 ~]# docker container run- d --name web01 -p 81:80 nginx

Test visit: http://192.168.56.14:81/

[email protected]:/# docker exec -it web01 bash< /span>

[email protected]:/# echo web01> /usr/share/nginx/html /index.html

2) Use docker to build the second nginx service

[[email protected]-node4 ~]# docker container run- d --name web02 -p 82:80 nginx

Test visit: http://192.168.56.14:82/

[email protected]:/# docker exec -it web02 bash< /span>

[email protected]:/# echo web02> /usr/share/nginx/html /index.html

[[email protected] ~]# yum -y install nginx

[[email Protected] ~]# vim /etc/nginx/nginx.conf< /span>

#### Modify nginx.conf to default to rotation ####



‘‘‘

# 1. Upstream is written by itself and must be placed outside the server

upstream myservers {

 server 192.168.56.14:81;

 server 192.168.56.14:82;

}



# 2. The server actually already has one by default, you only need to modify the configuration in the location and specify the forwarding proxy.

server {

 location / {

 proxy_pass http://myservers;

}

}

‘‘‘

[[email protected]-node4 nginx]# systemctl start nginx < /span>

upstream backserver {

 server 192.168.0.14;

 server 192.168.0.15;

}

upstream backserver {

 server 192.168.0.14 weight=3;

 server 192.168.0.15 weight=7;

}

upstream backserver {

 ip_hash;

 server 192.168.0.14:88;

 server 192.168.0.15:80;

}

upstream backserver {

 server server1;

 server server2;

 fair;

}

upstream backserver {

 server squid1:3128;

 server squid2:3128;

 hash $request_uri;

 hash_method crc32;

}