3Com 3CRUS2475 User Manual page 220

220 C 11: C
HAPTER ONFIGURING
S T
PANNING REE
the Forwarding state when the port link is up. Fast Link optimizes the
STP protocol convergence. STP convergence can take 30-60 seconds
in large networks.
Root Guard —
Restricts the interface from acting as the root port of the
■
switch.
Port State — Displays the current STP state of a port. If enabled, the
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port state determines what forwarding action is taken on traffic.
Possible port states are:
Forwarding — Indicates that the port forwards traffic while
■
learning MAC addresses.
Port Role — Displays the port role assigned by the STP algorithm to
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provide to STP paths. The possible field values are:
Root — Provides the lowest cost path to forward packets to the
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root switch.
Designated — The port or LAG through which the designated
■
switch is attached to the LAN.
Alternate — Provides an alternate path to the root switch from the
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root interface.
Backup — Provides a backup path to the designated port path
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toward the Spanning Tree leaves. Backup ports occur only when
two ports are connected in a loop by a point-to-point link, or when
a LAN has two or more connections connected to a shared
segment.
Disabled — The port is not participating in the Spanning Tree.
■
Speed — Indicates the speed at which the port is operating.
■
Path Cost — Indicates the port contribution to the root path cost. The
■
path cost is adjusted to a higher or lower value, and is used to forward
traffic when a path is re-routed.
Priority — Priority value of the port. The priority value influences the
■
port choice when a bridge has two ports connected in a loop. The
priority range is between 0 -240. The priority value is determined in
increments of 16.
Designated Bridge ID — Indicates the bridge priority and the MAC
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Address of the designated bridge.
Designated Port ID — Indicates the selected port priority and
■
interface.