Failed-error-during-websocket-handshake-connection-header-is-missing -

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 .

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

: Force websocket transport: io('url', { transports: ['websocket'] }) . proxy_set_header Upgrade $http_upgrade

Which or server framework are you currently using to host this application? proxy_set_header Connection "upgrade"

location /ws { proxy_pass http://your_backend_server; proxy_http_version 1.1; proxy_set_header Upgrade $http_upgrade; proxy_set_header Connection "upgrade"; } Use code with caution. Copied to clipboard 🕸️ Apache Configuration Fix