负载均衡的基本知识以及使用nginx进行负载均衡的简单例子

[root@kong ~]# docker run -d -p 7001:8080 liumiaocn/tornado:latest python /usr/local/bin/daemon.py "User Service 1: 7001"
ddba0abd24524d270a782c3fab907f6a35c0ce514eec3159357bded09022ee57
[root@kong ~]# docker run -d -p 7002:8080 liumiaocn/tornado:latest python /usr/local/bin/daemon.py "User Service 1: 7002"
95deadd795e19f675891bfcd44e5ea622c95615a95655d1fd346351eca707951
[root@kong ~]# 
[root@kong ~]# curl http://192.168.163.117:7001
Hello, Service :User Service 1: 7001
[root@kong ~]# 
[root@kong ~]# curl http://192.168.163.117:7002
Hello, Service :User Service 1: 7002
[root@kong ~]# 

[root@kong ~]# docker run -p 9080:80 --name nginx-lb -d nginx 
9d53c7e9a45ef93e7848eb3f4e51c2652a49681e83bda6337c89a3cf2f379c74
[root@kong ~]# docker ps |grep nginx-lb
9d53c7e9a45e    nginx           "nginx -g 'daemon ..."  11 seconds ago   Up 10 seconds    0.0.0.0:9080->80/tcp                         nginx-lb
[root@kong ~]#

http {
upstream nginx_lb {
  server 192.168.163.117:7001;
  server 192.168.163.117:7002;
}
server {
  listen    80;
  server_name www.liumiao.cn 192.168.163.117;
  location / {
    proxy_pass http://nginx_lb;
  }
}

[root@kong ~]# docker exec -it nginx-lb sh
# apt-get update
...省略
# apt-get install vim
...省略

# cat default.conf
server {
  listen    80;
  server_name localhost;
  #charset koi8-r;
  #access_log /var/log/nginx/host.access.log main;
  location / {
    root  /usr/share/nginx/html;
    index index.html index.htm;
  }
  #error_page 404       /404.html;
  # redirect server error pages to the static page /50x.html
  #
  error_page  500 502 503 504 /50x.html;
  location = /50x.html {
    root  /usr/share/nginx/html;
  }
  # proxy the PHP scripts to Apache listening on 127.0.0.1:80
  #
  #location ~ \.php$ {
  #  proxy_pass  http://127.0.0.1;
  #}
  # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
  #
  #location ~ \.php$ {
  #  root      html;
  #  fastcgi_pass  127.0.0.1:9000;
  #  fastcgi_index index.php;
  #  fastcgi_param SCRIPT_FILENAME /scripts$fastcgi_script_name;
  #  include    fastcgi_params;
  #}
  # deny access to .htaccess files, if Apache's document root
  # concurs with nginx's one
  #
  #location ~ /\.ht {
  #  deny all;
  #}
}
#

# cat default.conf
upstream nginx_lb {
  server 192.168.163.117:7001;
  server 192.168.163.117:7002;
}
server {
  listen    80;
  server_name www.liumiao.cn 192.168.163.117;
  #charset koi8-r;
  #access_log /var/log/nginx/host.access.log main;
  location / {
    #root  /usr/share/nginx/html;
    #index index.html index.htm;
    proxy_pass http://nginx_lb;
  }
  #error_page 404       /404.html;
  # redirect server error pages to the static page /50x.html
  #
  error_page  500 502 503 504 /50x.html;
  location = /50x.html {
    root  /usr/share/nginx/html;
  }
  # proxy the PHP scripts to Apache listening on 127.0.0.1:80
  #
  #location ~ \.php$ {
  #  proxy_pass  http://127.0.0.1;
  #}
  # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
  #
  #location ~ \.php$ {
  #  root      html;
  #  fastcgi_pass  127.0.0.1:9000;
  #  fastcgi_index index.php;
  #  fastcgi_param SCRIPT_FILENAME /scripts$fastcgi_script_name;
  #  include    fastcgi_params;
  #}
  # deny access to .htaccess files, if Apache's document root
  # concurs with nginx's one
  #
  #location ~ /\.ht {
  #  deny all;
  #}
}
#

[root@kong ~]# docker restart nginx-lb
nginx-lb
[root@kong ~]#

# cp default.conf default.conf.org
# vi default.conf
# diff default.conf default.conf.org
2,3c2,3
<   server 192.168.163.117:7001 weight=100;
<   server 192.168.163.117:7002 weight=200;
---
>   server 192.168.163.117:7001;
>   server 192.168.163.117:7002;
#

[root@kong ~]# docker restart nginx-lb
nginx-lb
[root@kong ~]#