What does "couldn't connect to host" mean?
In order to retrieve a web page, the client (in this case a Wormly monitoring node) needs to first establish a connection to your web server on TCP port 80 (for plain HTTP) or TCP port 443 (for TLS secured HTTPS).
This error indicates that your web server did not accept our TCP connection request, and hence the HTTP Request could not be performed.
Causes of this may include - but are not limited to:
- Crashed or failed web server processes
- Firewall mis-configuration
- Network or router failure
Troubleshooting steps
- Use the free HTTP test tool to verify if the problem persists. The test tool will provide diagnostic information showing the DNS resolution, TCP connection establishment, TLS / SSL encryption session creation and finally the HTTP request and response.
- Use the free remote PING tool to verify that the server or cloud instance hosting the web server is reachable.
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