curl -v -I http://connectivitycheck.gstatic.com/generate_204 2>&1 | grep "< HTTP" # Expected: < HTTP/1.1 204 No Content
Or a minimal Python HTTP server:
from http.server import HTTPServer, BaseHTTPRequestHandler class NoContentHandler(BaseHTTPRequestHandler): def do_GET(self): if self.path == '/generate_204': self.send_response(204) self.end_headers() HTTPServer(('', 80), NoContentHandler).serve_forever() connectivitycheck.gstatic.com/generate_204 is a simple, highly effective tool for automated network state detection. Its reliance on HTTP 204 No Content makes it bandwidth-free, cache-friendly, and universally interpretable. While primarily designed for Google’s ecosystems, it has become a de facto standard for connectivity checks across countless network devices and scripts. connectivitycheck gstatic generate 204
Do not block or alter responses to this endpoint in enterprise networks, as it degrades user experience on Android and Chromium devices without improving security. Appendix: Sample cURL Test curl -v -I http://connectivitycheck
# Nginx configuration for internal connectivity check location /generate_204 return 204; Do not block or alter responses to this