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Edge ports and edge port roles, Point-to-point ports – Brocade TurboIron 24X Series Configuration Guide User Manual

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Brocade TurboIron 24X Series Configuration Guide

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Configuring STP related features

Edge ports and edge port roles

The Brocade implementation of 802.1W allows ports that are configured as Edge ports to be
present in an 802.1W topology. (

Figure 65

). 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 65

Topology with edge ports

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.

Switch 1

Bridge priority = 600

Switch 2

Bridge priority = 1000

Switch 3

Bridge priority = 2000

Port2

Port2

Port3

Port3

Port3

Port2

Port5
Edge Port

Port5
Edge Port