nginx配置负载均衡

负载策略

1. 权重轮询：wrr 【weight round-robin】
2. ip_hash：
   nginx会根据客户端ip的hash结果选择一个真实服务器，而且每次都会固定访问这台服务器，可以解决session保存问题。
3. least_conn：当前活跃连接数越小，权重越大，优先选择。
4. 第三方负载策略，另查找资料
5. …

配置块

1. weight
2. max_fails
3. fail_timeout
4. down
5. backup
6. …

nginx.conf

重点关注 upstream 块里边的内容 upstream server_group { }

# For more information on configuration, see:
#   * Official English Documentation: http://nginx.org/en/docs/
#   * Official Russian Documentation: http://nginx.org/ru/docs/

#user nginx;
worker_processes auto;
error_log /usr/local/soft/nginx/logs/error.log;
pid /run/nginx.pid;

# Load dynamic modules. See /usr/share/doc/nginx/README.dynamic.
include /usr/share/nginx/modules/*.conf;

events {
    worker_connections 1024;
}

http {
    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log  /usr/local/soft/nginx/logs/access.log  main;

    sendfile            on;
    tcp_nopush          on;
    tcp_nodelay         on;
    keepalive_timeout   65;
    types_hash_max_size 2048;

    include             /usr/local/soft/nginx/conf/mime.types;
    default_type        application/octet-stream;

    # Load modular configuration files from the /etc/nginx/conf.d directory.
    # See http://nginx.org/en/docs/ngx_core_module.html#include
    # for more information.
    include /usr/local/soft/nginx/conf/conf.d/*.conf;

    # 定义一个服务器组
    upstream server_group {
        # 默认的轮询算法
        wrr;
        server 49.234.55.50:8080 weight=2 max_fails=3 fail_timeout=15;
        server 49.234.55.50:8081 down;
        server 49.234.55.50:8082 backup;
    }

    server {
        listen       80;
        server_name 159.75.79.151;
        root         /usr/share/nginx/html;

        # Load configuration files for the default server block.
        include /usr/local/soft/nginx/conf/default.d/*.conf;

       location /load_balancing_test {
            proxy_http_version 1.1;
            proxy_pass http://server_group/;
            proxy_set_header   Host    $host:$server_port;
            proxy_set_header   X-Real-IP   $remote_addr;
            proxy_set_header   X-Forwarded-For $proxy_add_x_forwarded_for;
            client_max_body_size  1000M;
        }
    }
}