| Description | This article describes how to troubleshoot STP issues in FortiLink over P2P topologies. |
| Scope | FortiSwitches managed by FortiGate via FortiLink. |
| Solution |
In some scenarios of FortiLink over P2P, there is a service provider environment between the Local switch and the remote switch.
In some scenarios, STP packets get encapsulated by the provider environment (for example GBPT) and then it is multicast to the remote switch.
Now these GBPT packets cannot be decapsulated on the FortiSwitch side and as a result, STP convergence will not work between remote switches which may cause a loop in the network. As in the below capture taken on the uplink interface of the remote switch, there are GBPT multicast packets instead of original STP packets sent from the source.
Make sure that STP packets transmitted from Local switches should not be manipulated or changed by the intermediate environment for correct STP convergence on remote switches. |
