C#大佬或nginx大佬帮忙看下这是哪方面问题？websocket问题-嘟嘟社区

我系统用的centos7用下面代码装的nginx

sudo rpm -Uvh http://nginx.org/packages/centos/7/noarch/RPMS/nginx-release-centos-7-0.el7.ngx.noarch.rpm

sudo yum install -y nginx

sudo systemctl start nginx&&sudo systemctl enable nginx

我使用signalR 跨域连接，本地测试没问题，本地html连接我的signalR 本地服务器。
放互联网上。提示这个错误。
Error: Failed to start the transport ‘WebSockets’: 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.

这应该不是我代码问题吧？本地测试都ok。
这是因为nginx默认不支持ws么？如果是的话，大概要怎么装ws，复杂么。