Dell PowerConnect FCS624S Configuration Guide - Page 273

Configuring STP related features 8 Edge ports and edge port roles The Dell implementation of 802.1W allows ports that are configured as Edge ports to be present in an 802.1W topology. (Figure 27). Edge ports are ports of a bridge that connect to workstations or computers. Edge ports do not register any incoming BPDU activities. Edge ports assume Designated port roles. Port flapping does not cause any topology change events on Edge ports since 802.1W does not consider Edge ports in the spanning tree calculations. FIGURE 27 Topology with edge ports Switch 1 Port2 Bridge priority = 600 Port3 Port2 Switch 2 Bridge priority = 1000 Port3 Port5 Edge Port Port2 Port3 Switch 3 Bridge priority = 2000 Port5 Edge Port However, if any incoming RST BPDU is received from a previously configured Edge port, 802.1W automatically makes the port as a non-edge port. This is extremely important to ensure a loop free Layer 2 operation since a non-edge port is part of the active RSTP topology. The 802.1W protocol can auto-detect an Edge port and a non-edge port. An administrator can also configure a port to be an Edge port using the CLI. It is recommended that Edge ports are configured explicitly to take advantage of the Edge port feature, instead of allowing the protocol to auto-detect them. Point-to-point ports To take advantage of the 802.1W features, ports on an 802.1W topology should be explicitly configured as point-to-point links using the CLI. Shared media should not be configured as point-to-point links. PowerConnect B-Series FCX Configuration Guide 231 53-1002266-01