API checks can be tricky to troubleshoot. Here are some common issues and solutions:

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Getting the Error: ESOCKETTIMEDOUT error

Sometimes API checks return this error, without any other information on what caused it.
  • This is a socket timeout error. Essentially there is no successful connection with the API at the TCP and/or DNS level. Then, Checkly is closing the connection after the usual 30 seconds timeout, because the server didn’t respond.
  • Usually the root cause for this error is intermittent network issues on the application side.
  • There will probably be no errors in the application logs, as it was not even possible to establish a connection.
  • The response headers will be empty. If Checkly doesn’t get a connection, there is nothing to send back, e.g. the response headers.

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Authentication Problems

Issue: 401/403 status codes, authorization errors Solutions:
  1. Verify API credentials are correct and active
  2. Check token expiration and refresh if needed
  3. Validate authentication headers format
  4. Test API manually with same credentials

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Timeout Issues

Issue: Requests timing out, slow responses Solutions:
  1. Check API server performance and load
  2. Verify network connectivity from monitoring locations
  3. Increase timeout thresholds if appropriate
  4. Investigate API infrastructure capacity

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Assertion Failures

Issue: Unexpected response content or format Solutions:
  1. Review actual API response vs. expected format
  2. Update assertions for API changes
  3. Check for environment-specific differences
  4. Validate test data and dependencies