Manual
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178 
The connections among the switches are shown in the above figure. All the switches run in the 
MSTP  mode  by  default,  their  bridge  priority,  port  priority  and  port  route  cost  are  all  in  the 
default values (equal). The default configuration for switches is listed below:  
Bridge Name 
SW1 
SW2 
SW3 
SW4 
Bridge MAC 
 Address 
…00-00-01 
…00-00-02 
…00-00-03 
…00-00-04 
Bridge Priority 
32768 
32768 
32768 
32768 
Port Priority 
port 1 
128 
128 
128 
port 2 
128 
128 
128 
port 3 
128 
128 
port 4 
128 
128 
port 5 
128 
128 
port 6 
128 
128 
port 7 
128 
128 
Route Cost 
port 1 
200000 
200000 
200000 
port 2 
200000 
200000 
200000 
port 3 
200000 
200000 
port 4 
200000 
200000 
port 5 
200000 
200000 
port 6 
200000 
200000 
port 7 
200000 
200000 
By default, the MSTP establishes a tree topology (in blue lines) rooted with SwitchA. The ports 
marked with “x” are in the discarding status, and the other ports are in the forwarding status. 
Configurations Steps: 
Step 1: Configure port to VLAN mapping: 
   Create VLAN 20, 30, 40, 50 in Switch2, Switch3 and Switch4. 
   Set ports 1-7 as trunk ports in Switch2 Switch3 and Switch4. 
Step 2: Set Switch2, Switch3 and Switch4 in the same MSTP:  
   Set Switch2, Switch3 and Switch4 to have the same region name as mstp. 
   Map VLAN 20 and VLAN 30 in Switch2, Switch3 and Switch4 to Instance 3; Map VLAN 
40 and VLAN 50 in Switch2, Switch3 and Switch4 to Instance 4. 
Step 3: Set Switch3 as the root bridge of Instance 3; Set Switch4 as the root bridge of Instance 
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