24-Port Layer 3 Switch Management Guide

S PANNING T REE A LGORITHM C ONFIGURATION
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• Trunk Member – Indicates if a port is a member of a trunk.
(STA Port Information only)
These additional parameters are only displayed for the CLI:
• Admin status – Shows if STA has been enabled on this interface.
• Path Cost – This parameter is used by the STA to determine the best
path between devices. Therefore, lower values should be assigned to
ports attached to faster media, and higher values assigned to ports with
slower media. (Path cost takes precedence over port priority.)
• Priority – Defines the priority used for this port in the Spanning Tree
Algorithm. If the path cost for all ports on a switch is the same, the port
with the highest priority (i.e., lowest value) will be configured as an active
link in the Spanning Tree. This makes a port with higher priority less
likely to be blocked if the Spanning Tree Algorithm is detecting network
loops. Where more than one port is assigned the highest priority, the port
with the lowest numeric identifier will be enabled.
• Designated root – The priority and MAC address of the device in the
Spanning Tree that this switch has accepted as the root device.
• Fast forwarding – This field provides the same information as Admin
Edge port, and is only included for backward compatibility with earlier
products.
• Admin Edge Port – You can enable this option if an interface is
attached to a LAN segment that is at the end of a bridged LAN or to an
end node. Since end nodes cannot cause forwarding loops, they can pass
Backup port receives more
useful BPDUs from the same
bridge and is therefore not
selected as the designated
port.
x
RR
ADB