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What Should I Do If Error Code 503 Is Displayed?

Error code 503 is returned during subscription debugging in the IoTDA console.

Check the following items:

  • If you call a subscription API, check whether the subscription is successful based on the response code. If 201 Created is returned, the API was called successfully. Otherwise, modify the request based on the error code and resend the request.
  • During debugging in the IoTDA console, you can view the message tracing information on the online debugging page to check whether the platform has successfully sent data.
  • Capture packets on the application and check whether the POST message from the platform is received.
  • Check if the server port corresponding to the IP address is enabled. Run the telnet command on another computer on the external network to check whether the IP address and port are enabled. If they are not enabled, change the IP address and port of the callback URL.
  • If a domain name is used in the subscription callback URL and is bound to multiple IP addresses, perform DNS resolution to confirm that the IP address is reachable.
  • If the subscription callback URL is an HTTPS address, the server certificate may be faulty or the CA certificate corresponding to the server certificate may have not been uploaded to the platform.

    During commissioning, ensure that the certificate creation process is correct and upload the certificate.

    For commercial use, apply for a certificate from the certificate authority and upload the certificate by referring to Loading the CA Certificate.

    If Check Common Name is selected during certificate upload, ensure that the domain name of the application is the same as the common name of the certificate. You can use the certificate verification tool to view the common name of the certificate.

Parent topic: Subscription and Push