FortiManager- while adding Forti device in FortiManager “A device with Serial Number already exists”


Recently we have deployed FortiManager in our organization. Here we have a single console of FortiManager and Forti Analyzer. Our Requirement is to add 10 no. of FortiGate Device and must have manage from FortiManager. The Forti device would have us advertised beforehand in Forti Analyzer. Now we have to add a Forti device to manage the policy in the FortiManager. However, when we are going to add the FortiGate Device in the FortiManager, Getting discover error “A device with Serial Number already exist”.

Solution applied.

FortiGate Firmware version                        : v6.0.4 build0163 (GA)

Forti Client Version                                       : 6.0.4

FortiManager                                                : v6.0.4-build0292 190109 (GA)


When endeavouring to add a Fortigate Device to FortiManager, the error message is shows “A Fortigate Unit with Serial Number FGXXXXXX is already exist”


This happens only when FortiGate device is Already Embedded/Added in Forti Logging Manager.


Who is already enrolled your FortiGate device in Forti logging manager; first, you have to delete it from the logging manager if already. After deleting, you have to add a FortiGate device to the Forti Manager. When Fortigate device added to FortiManager and automatically Fortigate device added to the Forti logging also. Here you will be having a question in mind that if the device has deleted from the logging manager, then logs of device will safe or not? For that, you are worried about your device’s logs will not be deleted.

# diagnose dvm device list

Find registry with Fortigate device serial number and perform the delete task.

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