Technical Tip: Remove a VLAN from FortiLink for Fortiswitch managed by FortiGate

By default, the FortiGate will sync and put VLANs back on the FortiLink after they're removed. Use the following commands on the FortiSwitch (not the FortiGate) to permanently remove VLANs:

# config switch trunk

edit "_FlInKxxxx"

set static-isl enable

set static-isl-auto-vlan disable

end

Reboot the FortiSwitch after the above command, then run the following:

# config switch interface

edit "xxxxxxx" (the ID of the FortiLink interface)

set allowed-vlans 1,xx,xx,4088-4094

end

It will still be possible to use the VLAN on the FortiSwitch, but it will be pruned off the FortiLink (trunk).