Users Guide

To change the port cost or priority of an interface, use the following commands.
• Change the port cost of an interface.
INTERFACE mode
spanning-tree rstp cost cost
The range is from 0 to 65535.
The default is listed in the previous table.
• Change the port priority of an interface.
INTERFACE mode
spanning-tree rstp priority priority-value
The range is from 0 to 15.
The default is 128.
To view the current values for interface parameters, use the show spanning-tree rstp command from
EXEC privilege mode.
Enabling SNMP Traps for Root Elections
and Topology Changes
To enable SNMP traps collectively, use this command.
Enable SNMP traps for RSTP, MSTP, and PVST+ collectively.
snmp-server enable traps xstp
Influencing RSTP Root Selection
RSTP determines the root bridge, but you can assign one bridge a lower priority to increase the likelihood that
it is selected as the root bridge.
To change the bridge priority, use the following command.
• Assign a number as the bridge priority or designate it as the primary or secondary root.
PROTOCOL SPANNING TREE RSTP mode
bridge-priority priority-value
• priority-value The range is from 0 to 65535. The lower the number assigned, the more likely this
bridge becomes the root bridge.
The default is 32768. Entries must be multiples of 4096.
Rapid Spanning Tree Protocol (RSTP) 811