Nginx FAQ

# 使用 http_host
proxy_set_header Host $http_host;
# 或者
proxy_set_header Host $host:$server_port;

nginx -V | grep stream_ssl_preread_module

stream {

  map $ssl_preread_server_name $targetBackend {
    ab.mydomain.com  upstream1.example.com:443;
    xy.mydomain.com  upstream2.example.com:443;
  }

  server {
    listen 443;

    proxy_connect_timeout 1s;
    proxy_timeout 3s;
    resolver 1.1.1.1;

    proxy_pass $targetBackend;
    ssl_preread on;
  }
}

stream {
  server {
    listen 443;
    proxy_pass backend.example.com:443;
  }
}