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Item Description
Root Guard
Indicates if the interface is acting as the root port of the switch. The possible
field values are:
z Enabled: Indicates Root Guard is enabled on the port
z Disabled: Indicates Root Guard is disabled on the port.
Port State
Displays the current STP state of a port. If enabled, the port state determines
what action is taken on traffic. Possible port states are:
z Disable: Indicates that STP is currently disabled on the port. The port
forwards traffic while learning MAC addresses.
z Blocking: Indicates that the port is currently blocked and cannot forward
traffic or learn MAC addresses. Blocking is displayed when Classic STP
is enabled.
z Listening: Indicates that the port is in listening mode. The port cannot
forward traffic nor can it learn MAC addresses.
z Learning: Indicates that the port is in learning mode. The port cannot
forward traffic, however it can learn new MAC addresses.
z Forwarding: Indicates that the port is in forwarding mode. The port can
forward traffic and learn new MAC addresses.
z Discarding: Indicates that the port is in discarding mode. The port is
listening to BPDUs, and discards any other frames it receives.
Port Role
Displays the port role assigned by the STP algorithm to provide to STP
paths. The possible field values are:
z Disable: Indicates that the port or LAG is currently disabled on the port
z Designated: The port or LAG through which the designated switch is
attached to the LAN.
z Alternate: Provides an alternate path to the root switch from the root
interface.
z Backup: With the designated port being blocked, the backup port
becomes the new designated port fast and begins to forward data
seamlessly.
z Root: Provides the lowest cost path to forward packets to the root switch.
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
Indicates the 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.
Link Type
Indicates whether a Point-to-Point link is established, or if the switch is
permitted to establish a Point-to-Point link. The possible field values are:
z Auto: Enables the switch to establish automatically point-to-point link.
z Point to Point: Indicates if a point-to-point link is currently established on
the port. Ports set to Full Duplex modes are considered Point-to-Point
port links.
z Shared: Enables the switch to establish a shared link.
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.
Forward Transitions
Indicates the number of times the port has changed from Forwarding state to
Blocking state.
