ZyXEL Communications 4728F User Manual

Chapter 13 Spanning Tree Protocol

XGS-4526/4528F/4728F User’s Guide

Bridge Priority

Set the priority of the Switch for the specific spanning tree instance. The 
lower the number, the more likely the Switch will be chosen as the root 
bridge within the spanning tree instance. 

Enter priority values between 0 and 61440 in increments of 4096 (thus 
valid values are 4096, 8192, 12288, 16384, 20480, 24576, 28672, 
32768, 36864, 40960, 45056, 49152, 53248, 57344 and 61440). 

VLAN Range

Enter the start of the VLAN ID range that you want to add or remove 
from the VLAN range edit area in the Start field. Enter the end of the 
VLAN ID range that you want to add or remove from the VLAN range 
edit area in the End field. 

Next click:

• Add - to add this range of VLAN(s) to be mapped to the MST 

instance. 

• Remove - to remove this range of VLAN(s) from being mapped to 

the MST instance. 

• Clear - to remove all VLAN(s) from being mapped to this MST 

instance. 

Enabled 
VLAN(s)

This field displays which VLAN(s) are mapped to this MST instance. 

Port

This field displays the port number. 

*

Settings in this row apply to all ports.

Use this row only if you want to make some settings the same for all 
ports. Use this row first to set the common settings and then make 
adjustments on a port-by-port basis. 

Note: Changes in this row are copied to all the ports as soon as you 

make them.

Active

Select this check box to add this port to the MST instance. 

Priority

Configure the priority for each port here.

Priority decides which port should be disabled when more than one port 
forms a loop in the Switch. Ports with a higher priority numeric value 
are disabled first. The allowed range is between 0 and 255 and the 
default value is 128.

Path Cost 

Path cost is the cost of transmitting a frame on to a LAN through that 
port. It is recommended to assign this value according to the speed of 
the bridge. The slower the media, the higher the cost - see 

 for more information.

Add

Click Add to save this MST instance to the Switch’s run-time memory. 
The Switch loses this change if it is turned off or loses power, so use the 
Save link on the top navigation panel to save your changes to the non-
volatile memory when you are done configuring.

Cancel

Click Cancel to begin configuring this screen afresh.

Instance

This field displays the ID of an MST instance. 

VLAN

This field displays the VID (or VID ranges) to which the MST instance is 
mapped. 

Active Port

This field display the ports configured to participate in the MST instance.

Table 33   Advanced Application > Spanning Tree Protocol > MSTP  (continued)