Troubleshooting Tip: How to fix the error message 'Fortimanager serial number is not matching' when connecting FortiGate to FortiManager v7.4.x
Description
This article describes how to connect FortiGate to FortiManager in case of running into the error message 'Fortimanager Serial Number is not matching' when trying to register a FortiGate to a FortiManager, and both are running on v7.4.x code.
Scope
FortiGate and FortiManager.
Solution
When configuring Central Management on FortiGate to have it managed via On-Premise FortiManager via GUI, it is easy to miss an essential and required parameter like FortiManager Serial Number because the text box for it is not shown on the page:
In the result after adding the FortiManager IP address, FortiOS will throw an error like this:
Similar behavior will be observed if adding FortiManager to FortiGate via CLI and not adding the serial number.
Any subsequent attempt to enter the FortiManager serial number will not have any effect on the FortiOS behavior, and it will still complain with the same error:
To fix this error, it is advised to remove the instance of FortiManager added earlier.
Via GUI:
Disable Central Management as shown below:
Via CLI:
Run the following commands to disable FortiManager to make sure that the central-management configuration section comes empty:
Then, complete FortiManager configuration only via CLI by submitting its IP address and serial number. Setting the source IP address is optional, and FortiGate will use its routing table to reach FortiManager:
The successful result will be followed by the warning message in the FortiGate GUI:
And the new unauthorized device appearing under FortiManager:
Related articles:
Troubleshooting Tip: How to solve the error message 'Could not connect to the FortiManager to retrieve its serial number' when connecting to FortiManager v7.2.5
Troubleshooting Tip: Unable to add VM into FortiManager due to 'Unsupported device model'