nginx/tengine 四层转发，根据源ip转发到指定ip端口？

你的需求是可以实现的。
需求示例：
当用户请求IP为192.168.2.11时把后端请求转发到192.168.2.11服务器的8080端口
当用户请求IP为192.168.2.12时把后端请求转发到192.168.2.12服务器的8080端口
当请求的IP不是192.168.2.11和192.168.2.12时，将请求全部转发到192.168.2.66的8080端口

通过nginx实现，nginx配置如下
server {
listen 80;
access_log /var/log/nginx/a.log;

location / {
proxy_ignore_client_abort on;
proxy_read_timeout 200s;
proxy_redirect off;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header Host $host;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
client_max_body_size 1000m;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "upgrade";

if ($remote_addr ~ "192.168.2.11")
{

proxy_pass http://ip11;
break;
}

if ($remote_addr ~ "192.168.2.12")
{

proxy_pass http://ip12;
break;
}

proxy_pass http://ip66;

}

}

upstream ip11 {
server 192.168.2.11:8080 max_fails=5 fail_timeout=10;
}

upstream ip12 {
server 192.168.2.12:8080 max_fails=5 fail_timeout=10;
}

upstream ip66 {
server 192.168.2.66:8080 max_fails=5 fail_timeout=10;
}