Nginx负载均衡中的Memcached缓存模块

server {
    location / {
        set            $memcached_key "$uri?$args";  # 设置Memcached缓存key
        memcached_pass 127.0.0.1:11211;              # 设置被代理Memcached地址
        error_page     404 502 504 = @fallback;      # 返回状态码404、502、504时跳入内部请求
    }
    location @fallback {
        proxy_pass     http://backend;               # 将请求转发给后端服务器
    }
}

yum -y install memcached
cat /etc/sysconfig/memcached
PORT="11211"                  # 端口
USER="memcached"
MAXCONN="1024"          # 最大连接数
CACHESIZE="64"              # 使用内存大小为64M
OPTIONS=""
systemctl start memcached

upstream backend {
    server 192.168.2.145:8190;                              # 后端PHP服务器IP
}
upstream memcached {
    hash $host$request_uri consistent;                      # 一致性hash
    server 192.168.2.145:11211;                             # Memcached服务器IP
    server 192.168.2.109:11211;                             # Memcached服务器IP
}
server {
    listen       8181;
    access_log logs/mem_access.log;
    set $memcached_key $host$request_uri;                   # 设置Memcached的key
    location / {
        memcached_connect_timeout 5s;             # 与Memcached建立连接超时时间为5s
        memcached_read_timeout 2s;                # 连续两次读的超时时间为2s
        memcached_send_timeout 2s;                # 连续两次写的超时时间为2s
        memcached_pass memcached;                 # 代理到Memcached集群
        add_header X-Cache-Satus HIT;             # 显示缓存命中状态
        add_header Content-Type 'text/html; charset=utf-8'; # 强制响应数据格式为html
    }
    error_page     404 502 504 = @fallback;
    location @fallback {
        proxy_set_header   X-Memcached-Key $memcached_key;  # 将memecached key传递
                                                            # 给PHP服务器
        proxy_pass     http://backend;                      # PHP服务器
    }
}