908 | Rapid Spanning Tree Protocolw w w . d e l l . c o m | s u p p o r t . d e l l . c o mInfluence RSTP Root SelectionThe Rapid Spanning Tree Protocol determines the root bridge, but you can assign one bridge a lowerpriority to increase the likelihood that it will be selected as the root bridge.To change the bridge priority, use the following command:A console message appears when a new root bridge has been assigned. Figure 44-8 shows the consolemessage after the bridge-priority command is used to make R2 the root bridge.Figure 44-8. bridge-priority Command ExampleSNMP Traps for Root Elections and Topology ChangesEnable SNMP traps for RSTP, MSTP, and PVST+ collectively using the command snmp-server enabletraps xstp.Task Command Syntax Command ModeAssign a number as the bridge priority or designate it as theprimary or secondary root.priority-value range: 0 to 65535. The lower the numberassigned, the more likely this bridge will become the rootbridge. The default is 32768. Entries must be multiples of4096.bridge-priority priority-value PROTOCOLSPANNING TREERSTPFTOS(conf-rstp)#bridge-priority 409604:27:59: %RPM0-P:RP2 %SPANMGR-5-STP_ROOT_CHANGE: RSTP root changed. My Bridge ID:4096:0001.e80b.88bd Old Root: 32768:0001.e801.cbb4 New Root: 4096:0001.e80b.88bdNew root bridge IDOld root bridge ID
