link is up. Fast Link optimizes the STP protocol convergence. STP convergence can take
—Enabled — Port Fast is enabled.
—Auto — Port Fast mode is enabled a few seconds after the interface becomes active.
—Disabled — Port Fast is disabled.
•Root Guard — Prevents devices outside the network core from being assigned the spanning tree root.
•Port State — Displays the current STP state of a port. If enabled, the port state determines what forwarding action is taken on traffic. Possible port states are:
—Forwarding — Indicates that the port can forward traffic or learn MAC addresses.
—Disabled — Indicates that STP is currently disabled on the port. The port forwards traffic while learning MAC addresses.
—Discarded — Indicates that the port is currently blocked and cannot forward traffic or learn MAC addresses.
•Port Role — Displays the port role assigned by the STP algorithm to provide to STP paths. The possible field values are:
—Root — Provides the lowest cost path to forward packets to the 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 root interface.
—Backup — Provides a backup path to the designated port path toward the Spanning Tree leaves. Backup ports occur only when two ports are connected in a loop by a
—Disable — 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 value is between 0
•Designated Bridge ID — Indicates the bridge priority and the MAC Address of the designated bridge.
•Designated Port ID — Indicates the selected port priority and interface.
•Designated Cost — Indicates the cost of the port participating in the STP topology. Ports with a lower cost are less likely to be blocked if STP detects loops.
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