If you are using Nginx as a reverse proxy, you must explicitly tell it to forward the Upgrade and Connection headers. By default, Nginx does not do this. Add or update your location block in your nginx.conf file:
: Force websocket transport: io('url', { transports: ['websocket'] }) . If you are using Nginx as a reverse
Which or server framework are you currently using to host this application? Which or server framework are you currently using
Here are the most common solutions based on your infrastructure: 🚀 Nginx Configuration Fix { transports: ['websocket'] }) .
Ensure mod_proxy and mod_proxy_wstunnel are enabled. Use a RewriteRule in your VirtualHost to pass WebSocket traffic:
The error occurs when a client tries to establish a WebSocket connection, but a network intermediary (like a reverse proxy or load balancer) strips out the required HTTP headers needed to upgrade the connection from standard HTTP to WebSockets .