nginx config_error ai_generated true

WebSocket: connection upgrade failed through proxy

ID: nginx/websocket-proxy-config

Also available as: JSON · Markdown
82%Fix Rate
86%Confidence
3Evidence
2023-01-01First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
1 active — — —

Root Cause

Nginx not properly proxying WebSocket upgrade headers.

generic

Workarounds

  1. 92% success Set upgrade headers: proxy_set_header Upgrade ; proxy_set_header Connection "upgrade"
  2. 90% success Set proxy_http_version 1.1 for WebSocket locations

Dead Ends

Common approaches that don't work:

  1. Use HTTP/1.0 for WebSocket proxy 88% fail

    Doesnt support upgrade

  2. Set all proxy headers globally 72% fail

    May affect non-WS traffic