Manual
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Boundary Ports. They only process CIST related information and abandon MSTI information.  
11.1.2 Port Roles 
The MSTP bridge assigns a port role to each port which runs MSTP. 
CIST port roles: Root Port, Designated Port, Alternate Port and Backup Port 
On top of those roles, each MSTI port has one new role: Master Port. 
The port roles in the CIST (Root Port, Designated Port, Alternate Port and Backup Port) are 
defined in the same ways as those in the RSTP.  
11.1.3 MSTP Load Balance 
In a MSTP region, VLANs can by  mapped to various instances. That can form various 
topologies. Each instance is independent from the others and each distance can have its own 
attributes  such  as  bridge  priority  and  port  cost etc.  Consequently,  the  VLANs  in  different 
instances have their own paths. The traffic of the VLANs are load-balanced. 
11.2 MSTP Configuration Task List 
MSTP configuration task list: 
1. Enable the MSTP and set the running mode 
2. Configure instance parameters 
3. Configure MSTP region parameters 
4. Configure MSTP time parameters 
5. Configure the fast migrate feature for MSTP 
6. Configure the format of port packet 
7. Configure the spanning-tree attribute of port 
8. Configure the snooping attribute of authentication key 
9. Configure the FLUSH mode once topology changes 
1. Enable MSTP and set the running mode 
Command 
Explanation 
Global Mode and Port Mode 
spanning-tree 
no spanning-tree 
Enable/Disable MSTP. 
Global Mode 
spanning-tree mode {mstp|stp|rstp} 
no spanning-tree mode 
Set MSTP running mode. 
Port Mode 
spanning-tree mcheck 
Force port migrate to run under MSTP. 










