Day43-七层+四层负载均衡

1.七层负载均衡

1.根据url调度不同的集群

10.0.0.5
10.0.0.7 /pass
10.0.0.8 /user
1.web01和web02配置相同 (只不过代码不一样)

[root@web01 conf.d]# cat url.oldxu.com.conf 
server {
    listen 80;
    server_name url.oldxu.com;
    root /code;

    location / {
        index index.html;
    }
}

2.lb配置

[root@lb01 conf.d]# cat proxy_url.oldxu.com.conf 
upstream user {
    server 172.16.1.8;
}
upstream pass {
    server 172.16.1.7;
}

server {
    listen 80;
    server_name url.oldxu.com;
    location / {
        proxy_pass http://user;
        include proxy_params;
    }
    location /user {
                proxy_pass http://user;
                include proxy_params;
    }
    location /pass {
                proxy_pass http://pass;
                include proxy_params;
    }
}
[root@lb01 conf.d]# systemctl restart nginx

PS: 在使用proxy_pass反向代理时,最后结尾添加/和不添加/有什么区别?

1.不添加 /
用户如果请求: http://url.oldxu.com/user
会被代理至后端: http://url.oldxu.com/user

1.添加 /
用户如果请求: http://url.oldxu.com/user
会被代理至后端: http://url.oldxu.com/

2.根据设备调度不同的集群 ( 浏览器 ) ( 手机 )

10.0.0.5
10.0.0.7 pc
10.0.0.8 phone
1.所有的web都需要配置 ( 代码不一样)
[root@web01 conf.d]# cat /etc/nginx/conf.d/agent.oldxu.com.conf

server {
    listen 80;
    server_name agent.oldxu.com;
    root /code;

location / {
        index index.html;
    }

}

2.代理的配置

[root@lb01 conf.d]# cat proxy_agent.oldxu.com.conf 
upstream pc {
    server 172.16.1.7:80;
}

upstream phone {
    server 172.16.1.8:80;
}

server {
    listen 80;
    server_name agent.oldxu.com;
    location / {
        #默认都走pc
        proxy_pass http://pc;
        include proxy_params;
        default_type text/html;
        charset utf-8;

如果是安卓或iphone,则走phone
        if ( $http_user_agent ~* "android|iphone|iPad" ) {
            proxy_pass http://phone;
        }
如果是IE浏览器,要么拒绝,要么返回一个好的浏览器下载页面
        if ( $http_user_agent ~*  "MSIE" ) {
            return 200 '<a href="http://download.xuliangwei.com/gitlab-ce-8.3.4-ce.0.el7.x86_64.rpm" target="_blank">点击下载正版浏览器google.exe</a>';
        }
    }
}

2.四层负载均衡

1.什么是四层 OSI 传输层 TCP/IP UDP/TCP

四层是基于转发方式:

2.四层负载均衡使用场景

1.四层负载均衡 + 七层负载均衡
2.dns + 多机房 + 四层负载均衡+七层负载均衡

3.SOA 松耦合架构

    登录      passport.jd.com
    注册      reg.jd.com
    商品详情    pro.jd.com

4.基于端口的转发

                nginx 7层        web01       MySQL
nginx 4层  +                     web02       NFS
                nginx 7层        web03       Redis

5.nginx是1.9版本以后才引入的四层负载均衡

stream模块实现,但stream不能出现在http层
--with-stream
-with-stream_ssl_module
-with-stream_realip_module

stream {
    upstream backend {
        hash $remote_addr consistent;
        server backend1.example.com:12345 weight=5;
        server 127.0.0.1:12345 max_fails=3 
        server unix:/tmp/backend3;
    }
    server {
        listen 12345;
        proxy_connect_timeout 1s;
        proxy_timeout 3s;
        proxy_pass backend;
    }
}

3.nginx四层+nginx七层+web集群--->场景

四层负载均衡基本配置

1.定义四层配置文件路径

[root@lb-4 nginx]# vim /etc/nginx/nginx.conf
include /etc/nginx/conf.c/*.conf;

2.进行初始化操作

[root@lb-4 ~]# rm -f /etc/nginx/conf.d/default.conf
[root@lb-4 nginx]# mkdir /etc/nginx/conf.c

3.配置四层负载均衡

[root@lb-4 ~]# cat /etc/nginx/conf.c/all.conf
stream {
    upstream blog {
        server 172.16.1.5:80;
        server 172.16.1.6:80;
    }
    server {
        listen 80;
        proxy_pass blog;
        proxy_timeout 3s;
        proxy_connect_timeout 3s;
    }
}

基于端口的转发

需求: 用户连接10.0.0.4的6666端口,其实连接的是172.16.1.7的22/TCP端口
需求: 用户连接10.0.0.4的5555端口,其实连接的是172.16.1.51的3306/TCP端口

[root@lb-4 conf.c]# cat blog.oldxu.com.conf
stream {
    upstream ssh {
        server 172.16.1.7:22;
    }
    upstream mysql {
        server 172.16.1.51:3306;
    }
    
    server {
        listen 6666;
        proxy_pass ssh;
    }

    server {
        listen 5555;
        proxy_pass mysql;
    }
}

4.四层负载均衡怎么记录日志 必须在stream层,不能出现在http层

log_format  proxy '$remote_addr -  [$time_local]
            '   "$upstream_addr" 

    access_log /var/log/nginx/tcp.log proxy;