678 Spanning Tree Commandsport. In this way, the root guard enforces the position of the root bridge. InMSTP scenario the port may be designated in one of the instances whilebeing alternate in the CIST, and so on. Root guard is a per port (not a per portper instance command) configuration so all the MSTP instances this portparticipates in should not be in root role.STP BPDU Filtering - STP BPDU filtering applies to all operational edgeports. Edge Port in an operational state is supposed to be connected to hoststhat typically drop BPDUs. If an operational edge port receives a BPDU, itimmediately loses its operational status. In that case, if BPDU filtering isenabled on this port then it drops the BPDUs received on this port.STP BPDU Flooding - STP BPDU flooding feature applies to the STPdisabled switch. To enable BPDU flooding on a port, STP should be disabledon the switch administratively. When this feature is enabled on the switch, itfloods all the ports with the BPDU flood feature enabled on it.Commands in this ChapterThis chapter explains the following commands:clear spanning-treedetected-protocolsspanning-treeauto-portfastspanning-tree max-agespanning-tree portfastbpdufilter defaultexit (mst) spanning-tree bpdufloodingspanning-tree max-hopsspanning-tree portfastdefaultinstance (mst) spanning-treebpdu-protectionspanning-treemodespanning-tree port-priorityname (mst) spanning-tree cost spanning-tree mstconfigurationspanning-tree priorityrevision (mst) spanning-treedisablespanning-tree mstcostspanning-tree tcnguardshow spanning-tree spanning-treeforward-timespanning-tree mstport-priorityspanning-tree transmithold-countshow spanning-treesummaryspanning-treeguardspanning-tree mstpriorityspanning-tree spanning-treeloopguardspanning-treeportfast
