SGS-6341-Series User Manual

22-126
Switch4(config)#spanning-tree
Switch4(config)#spanning-tree mst 4 priority 0
After the above configuration, Switch1 is the root bridge of the instance 0 of the entire network.
In the MSTP region which Switch 2, Switch 3 and Switch 4 belong to, Switch2 is the region root
of the instance 0, Switch3 is the region root of the instance 3 and Switch 4 is the region root of
the instance 4. The traffic of VLAN 20 and VLAN 30 is sent through the topology of the
instance 3. The traffic of VLAN 40 and VLAN 50 is sent through the topology of the instance 4.
And the traffic of other VLANs is sent through the topology of the instance 0. The port 1 in
Switch 2 is the master port of the instance 3 and the instance 4.
The MSTP calculation generates 3 topologies: the instance 0, the instance 3 and the instance
4 (marked with blue lines). The ports with the mark “x” are in the status of discarding. The other
ports are the status of forwarding. Because the instance 3 and the instance 4 are only valid in
the MSTP region; the following figure only shows the topology of the MSTP region.
SW1
SW2
SW3
SW4
1
1 1X
2
2 2
3X3
4
4
5
5X
6
7
6X
7X
Figure 22-3: The Topolog
y Of the Instance 0 after the MSTP Calculation
2 2
3X 3
SW2
4 6
SW3
5 7
4X
6
5X 7X
SW4
Figure 22
-4:
The
T
opolo
g
y Of the Instance 3 after the MSTP Calculation
User’s Manual of SGS-6341 series