Configuring Path Cost - Cisco Catalyst 2960-XR Configuration Manual

Configuring Multiple Spanning-Tree Protocol
DETAILED STEPS
Command or Action
Step 1
configure terminal
Example:
Switch# configure terminal
Step 2 interface interface-id
Example:
Switch(config)# interface
GigabitEthernet1/0/1
Step 3
spanning-tree mst instance-id port-priority
priority
Example:
Switch(config-if)# spanning-tree mst 0
port-priority 64
Step 4
end
Example:
Switch(config-if)# end
The show spanning-tree mst interface interface-id privileged EXEC command displays information only
if the port is in a link-up operative state. Otherwise, you can use the show running-config interface privileged
EXEC command to confirm the configuration.
Related Topics
Specifying the MST Region Configuration and Enabling MSTP, on page 59
Configuring Path Cost, on page 65

Configuring Path Cost

The MSTP path cost default value is derived from the media speed of an interface. If a loop occurs, the MSTP
uses cost when selecting an interface to put in the forwarding state. You can assign lower cost values to
interfaces that you want selected first and higher cost values that you want selected last. If all interfaces have
the same cost value, the MSTP puts the interface with the lowest interface number in the forwarding state and
blocks the other interfaces.
OL-29424-01
Purpose
Enters the global configuration mode.
Specifies an interface to configure, and enters interface configuration
mode.
Configures port priority.
• For instance-id, you can specify a single instance, a range of
instances separated by a hyphen, or a series of instances
separated by a comma. The range is 0 to 4094.
• For priority, the range is 0 to 240 in increments of 16. The
default is 128. The lower the number, the higher the priority.
The priority values are 0, 16, 32, 48, 64, 80, 96, 112, 128, 144,
160, 176, 192, 208, 224, and 240. All other values are rejected.
Returns to privileged EXEC mode.
Catalyst 2960-XR Switch Layer 2 Configuration Guide, Cisco IOS Release 15.0(2)EX1

Configuring Path Cost

65