Nginx负载均衡策略 - weight 轮询加权

配置

$ vim $NGINX_HOME/conf/nginx.conf
worker_processes  auto;
events {
    use  epoll;
    worker_connections  65535;
}
http {
    upstream aidan.org{
        server 127.0.0.1:8881 weight=3;
        server 127.0.0.1:8882 weight=2;
        server 127.0.0.1:8883 weight=1;
    }
    server {
        listen       80;
        server_name  aidan.org;
        location / {
            proxy_pass  http://aidan.org;
            proxy_set_header  Host  $host;
            proxy_set_header  X-Real-IP  $remote_addr;
        }
    }
}
$ nginx -s reload

测试一下

[root@localhost ~]# curl aidan.org/a/a
hello nginx,I'm 8881 Server.nginx host is aidan.org,your realIp is 127.0.0.1
[root@localhost ~]# curl aidan.org/a/a
hello nginx,I'm 8882 Server.nginx host is aidan.org,your realIp is 127.0.0.1
[root@localhost ~]# curl aidan.org/a/a
hello nginx,I'm 8881 Server.nginx host is aidan.org,your realIp is 127.0.0.1
[root@localhost ~]# curl aidan.org/a/a
hello nginx,I'm 8883 Server.nginx host is aidan.org,your realIp is 127.0.0.1
[root@localhost ~]# curl aidan.org/a/a
hello nginx,I'm 8882 Server.nginx host is aidan.org,your realIp is 127.0.0.1
[root@localhost ~]# curl aidan.org/a/a
hello nginx,I'm 8881 Server.nginx host is aidan.org,your realIp is 127.0.0.1

发现8881出现了3次，8882出现2次，8883出现1次，权重比为3:2:1

小结

权重负载均衡需要使用weight指令定义
权重越高分配到的请求数量越多
此策略可以与最少连接负载和ip哈希策略结合使用;
此策略适合服务器的硬件配置差别较大的情况
权重其实就是轮询，只是轮询时加上个权重因素；不配置权重时权重为1：1：1罢了