Created on
‎06-13-2025
05:54 AM
Edited on
‎12-12-2025
01:52 AM
By
Jean-Philippe_P
| Description | This article describes the various errors that may be encountered while adding a new FortiGate to FortiManager, and the possible solutions. |
| Scope | FortiGate, FortiManager. |
| Solution |
When onboarding FortiGate to FortiManager, it is usually a seamless process, but issues may occur for various reasons. In this article, the most common issues seen are discussed along with their solutions.
To start troubleshooting the issue, review the event logs on the FortiManager, as well as run fgfmsd debugs, which gives a direction to look to find the root cause of the issue. Follow the instructions in Technical Tip: How to troubleshoot connectivity issues between FortiGate and FortiManager to run fgfmsd debugs on the FortiManager.
Scenario 1: When trying to add a FortiGate to FortiManager, an error message 'unregistered device ignored' may occur in the FortiManager Fgfmsd debugs. This error occurs if 'fgfm-deny-unknown' is enabled on the FortiManager. To resolve this, either follow the special instructions to add FortiGate to FortiManager as described in the following KB article or disable this setting:
config system global
Instructions to add FortiGate to FortiManager with fgfm-deny-unknown enable: Technical Tip: How to add FortiGate with its current config to FortiManager when 'set fgfm-deny-unkn....
Debug snippet:
": "<unknown>", "version": 700}, "from": 1}, "url": "dvm\/cmd\/manage\/device"}], "session": -1} bind /var/tmp/fgfm/.fos.FG101F1111111111.rpc-FMG-0000000000-VLW1Gc OK.
Scenario 2: In this scenario, FortiManager is showing an 'unknown CA' error in the debugs. This error could be seen on the FortiManager while adding a new FortiGate to FortiManager, and, for example, an intermediate CA is missing on the FortiManager. Ensure that all necessary CA certificates are present on the FortiManager to resolve this issue.
Debugs:
In FortiManager v7.4.6, the 'fgfm-peercert-withoutsn' setting has been removed, so the verification cannot be disabled. Ensure that the FortiGate certificate contains the serial number in either the CN or SAN. Note that FortiManager expects the serial number in the CN of the FortiGate certificate on FortiManager v7.4.6. This behavior is fixed in FortiManager v7.4.7, where a certificate can be created with the serial number in the SAN, and it should work.
To validate that on FortiGate, go to System -> Certificates, review the subject of the Certificate 'Fortinet_Factory', and ensure that the CN is showing the serial number of the FortiGate
If the CN is showing as "FortiGate" instead, then run the below command in FortiGate CLI :
execute vm-license
If it is a hardware FortiGate, apply the following command:
FortiGate (root)# execute vpn certificate local generate default-ssl-key-certs
FortiGate (root)# get vpn certificate local details
Note: If FortiManager is configured to use fgfm-peercert-withoutsn on v 7.4.5 (or older) and an upgrade is made to v7.4.6, FortiManager will encounter the same error in the debugs after the upgrade, because fgfm-peercert-withoutsn is removed and not available on v7.4.6: Release Notes: 7.4.6 Special Notices. Debugs:
Scenario 4: Sometimes, when adding a device, there might be an issue with the configuration present on the device, which can prevent the addition of a device to FortiManager.
To check and confirm if there is an issue with the configuration, the following commands can be run on FortiManager.
This command will load the configuration and comment where it finds the invalid data source. This configuration needs to be corrected before attempting to add the device again. |
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