最近测试将Blazor部署到Docker镜像，并使用Nginx进行集成，部署看上去没有问题，可在浏览器控制台发现如下问题：
Error: Failed to start the connection: Error: WebSocket failed to connect. The connection could not be found on the server, either the endpoint may not be a SignalR endpoint, the connection ID is not present on the server, or there is a proxy blocking WebSockets. If you have multiple servers check that sticky sessions are enabled.
应该是Nginx的配置问题，解决方案是在Nginx的配置中设置如下参数：

  proxy_http_version 1.1;
  proxy_set_header Upgrade $http_upgrade;
  proxy_set_header Connection "upgrade";

这里的关键是将Connection 设置为 "upgrade"。