Troubleshooting Tip: FortiLink Topology display issue observed on the FortiGate GUI after FortiSwitch upgrade to v7.4.7 (or later) or v7.6.2 (or later)

This issue impacts FortiGates running any version of FortiOS that are managing one or more FortiSwitch units operating on FortiSwitch v7.4.7 (or later) or v7.6.2 (or later).

The issue happens when any managed switch has more than five trunk members; the Topology view on the FortiGate may display incorrectly. However, this visual issue does not affect data traffic.

This issue impacts FortiGates running any version of FortiOS that are managing one or more FortiSwitch units operating on FortiSwitch v7.4.7 (or later) or v7.6.2 (or later).

The issue happens when any managed switch has more than five trunk members; the Topology view on the FortiGate may display incorrectly. However, this visual issue does not affect data traffic.

This issue is fixed in FortiOS versions 7.4.9 and 7.6.4 and later, and FortiSwitch versions 7.4.8 and 7.6.5 and later.

Both FortiGate and FortiSwitches should run in the mentioned versions to avoid the issue.

Workaround:

• Downgrade FortiSwitch to v7.6.1 or v7.4.6.

Or:

• Limit the total number of trunk member ports to five or fewer on the affected switch.

Or:

• Change the FortiLink management mode to HTTPS on the affected switch.

Note: If topology display issues are still observed after upgrading to FortiOS 7.4.9, they may also originate from the FortiSwitch side in certain cases. FortiSwitch OS 7.6.6 GA includes additional topology‑related fixes, and upgrading to this release is recommended.

Related articles:

• Technical Tip: How to share topology diagram for FortiSwitches managed via FortiLink for larger deployments
  
• Technical Tip: Export physical or logical topology to PDF