Spanning-Tree Operation 
802.1s Multiple Spanning Tree Protocol (MSTP) 
Configuring MST Instance Per-Port Parameters 
Command  Page 
spanning-tree instance < 1..16 > < port-list > path-cost  6-66 
< auto | 1..200000000 > 
spanning-tree instance < 1..16 > < port-list > priority < priority-multiplier  >  6-67 
spanning-tree < port-list > priority < priority-multiplier >  6-68 
Syntax:  spanning-tree instance < 1..16 > [e] < port-list > path-cost < auto | 
1..200000000 > 
This command assigns an individual port cost for the 
specified MST instance. (For a given port, the path cost setting 
can be different for different MST instances to which the port 
may belong.) The switch uses the path cost to determine which 
ports are the forwarding ports in the  instance; that is which 
links to use for the active topology of the instance and which 
ports to block.  The settings are either auto or in a range from 
1 to 200,000,000. With the auto setting, the switch calculates 
the path cost from the link speed: 
10 Mbps — 2000000 
100 Mbps — 200000 
1 Gbps — 20000 
(Default: Auto) 
6-66