Configuring Spanning Tree Bridge Priority
Refer to Figure Spanning Tree Topology. All switches must be in default configurations. After the topology stabilizes, switch A is elected as the Root since it has the least MAC address. All ports of all switches except Port 2 of switch C are in forwarding state. Port 2 of switch C has been detected as an alternate port and is in discarding state.
Configuring Spanning Tree Path Cost
Refer to Figure Spanning Tree Topology. All switches are configured for STP compatible using spanning-tree compatibility stp in Global Configuration mode. After the topology stabilizes and Switch A is elected as Root, the ports of all switches except Port 2 of Switch C are in forwarding state. Port 2 of Switch C is an alternate port, and it is in discarding state.
Configuring Spanning Tree Port Priority
Refer to Figure Spanning Tree Topology. All switches are configured for STP compatible using the “spanning-tree compatibility stp” Global Configuration mode command. After the topology stabilizes, Switch A is elected as Root and all ports of all switches except Ports 2 and 3 (alternate, discarding) of Switch C are in forwarding state.
Configuring Spanning Tree Link Type
If a port is configured as point-to-point link and its port role is designated, then IS5Com RSTP negotiates a rapid transition to forwarding with the other port by using proposal-handshake agreement mechanism to ensure that the topology is loop free. By default, if the interface is full-duplex, it is considered to have a point to point connection. If the interface is half duplex, then it is considered to have a shared connection. This default setting of link type can be overridden to enable rapid transition to forwarding state.