Fortinet 5003 Benutzerhandbuch

Add spanning tree instance 5 for packets from the external networks. Add VLAN 
tags 101 to this spanning tree instance. Set the priority of this spanning tree 
instance to 5, the same as instance 3.

spanning-tree instance 5 vlan 101
spanning-tree instance 5 priority 5

The FortiSwitch-5003A board in slot 1 requires the following configuration 
settings:

Disable communication between the FortiSwitch-5003A boards:

config switch fabric-channel physical-port

edit slot-2/1

set status down

end

Create an MSTP configuration that includes the same name and revision as was 
added to the external switch. For example, if the name is tree_1 and the revision 

is 1:

config switch fabric-channel stp settings

set name "tree_1"
set revision 1

end

Add two spanning tree instances numbered the same as the instances added to 
the switch (3 and 5). Add the VLAN tags to the instances and set their priority 
values to 4096:

config switch fabric-channel stp instance

edit 3

set priority 4096
set vlan-range 100

next
edit 5

set priority 4096
set vlan-range 101

end

Add a trunk named trunk_345 that aggregates backplane slots 3, 4, and 5:

config switch fabric-channel trunk

edit "trunk_345"

set members "slot-3" "slot-4" "slot-5"

end

Allow VLAN packets on the FortiSwitch-5003A F5 front panel interface and the 
trunk:

config switch fabric-channel interface

edit "f5"

set allowed-vlans 1,100-101

next
edit "trunk_345"

set allowed-vlans 1,100-101

end

Note: The priority values of both spanning tree instances should be lower on the 
FortiSwitch-5003A board in slot 1 than on the board in slot 2 so that MSTP directs all traffic 
to the board in slot 1.