Failed to retrieve a CA certificate
Symptom
Failed to retrieve a CA certificate.
Analysis
The network connection is not proper. For example, the network cable might be damaged or loose.
No trusted CA is specified.
The URL of the registration server for certificate request is not correct or not configured.
No authority is specified for certificate request.
The system clock of the switch is not synchronized with that of the CA.
Solution
Make sure the network connection is physically proper.
Check that the required commands are configured properly.
Use the ping command to verify that the RA server is reachable.
Specify the authority for certificate request.
Synchronize the system clock of the switch with that of the CA.