nginx - 基于 nginx 上游块中的 IP 重定向流量

Question

我想将来自 IP : 1.1.1.1 的流量重定向到上游块中的 server2 ，只有当 server2 关闭时，流量才应该路由到 server1

upstream backendServer {
    #ip_hash;
    server localhost:3000; #server1
    server localhost:3100; #server2 (traffic from 1.1.1.1 should route here unless and until server2 is closed)
    }

server {
    listen 80;
    server_name server_name;
    rewrite ^ https://$host$request_uri? permanent;
}

server {
    listen 443;
    ssl on;
    ssl_certificate server_name.crt;
    ssl_certificate_key server_name.txt;

    server_name server_name;
    index index.html index.htm index.nginx-debian.html;
    #root /home/ubuntu/server_name;

    location / {
        proxy_pass http://backendServer;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        proxy_set_header Host $host;
        proxy_cache_bypass
        $http_upgrade;
    }
}