FortiSwitch
FortiSwitch: secure, simple and scalable Ethernet solutions
yabhishek
Staff
Staff
Article Id 354556
Description This article describes how to form FortiLink trunks automatically and to avoid flapping of trunks.
Scope FortiSwitches managed by FortiLink.
Solution
The FortiLink ISL/ICL link between two switches creates trunks on each switch automatically with respective member ports.
 
The lldp-profile on peer ports should be default-auto-isl, for example:
 
config switch physical-port
    edit "port10"
        set lldp-profile "default-auto-isl"     
    next
end
 
If there will be any need to add the extra link then this new port should not be added manually to the trunk. The port will be recognized and added to the trunk by the switch.
 
Refer to the below diagram:
 

automatic-trunk.png

 

 

Adding the member ports manually can cause trunk flapping or packet loss in the link.