Dell PowerConnect 3524P User Manual page 337

• Root Guard — Prevents devices outside the network core from being assigned the spanning tree root.
– Checked — Root guard is enabled on the port.
– Unchecked — Root guard is disabled on the port.
• LAG State — Current STP state of a LAG. If enabled, the LAG state determines what forwarding
action is taken on traffic. If the bridge discovers a malfunctioning LAG, the LAG is placed in the
Broken state. Possible LAG states are:
– Disabled — STP is currently disabled on the LAG. The LAG forwards traffic while learning
MAC addresses.
– Blocking — The LAG is blocked and cannot be used to forward traffic or learn MAC addresses.
– RSTP Discarding State — In this state the port does not learn MAC addresses and do not forward
frames.
– This state is union of Blocking, and Listening state introduced in STP (802.1.D).
– Listening — The LAG is in the listening mode and cannot forward traffic or learn MAC addresses.
– Learning — The LAG is in the learning mode and cannot forward traffic, but it can learn new
MAC addresses.
– Forwarding — The LAG is currently in the forwarding mode, and it can forward traffic and learn
new MAC addresses.
– Broken — The LAG is currently malfunctioning and cannot be used for forwarding traffic.
• Role — Indicates the LAG role assigned by the STP algorithm that provides STP paths. The possible
field values are:
– Root — Provides the lowest cost path to forward packets to root switch.
– Designated — Indicates that the via which the designated switch is attached to the LAN.
– Alternate — Provides an alternate LAG 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 point-to-point link. Backup
ports also occur when a LAN has two or more connections connected to a shared segment.
– Disabled — Indicates the LAG is not participating in the Spanning Tree.
• Path Cost (1-200000000) — Amount the LAG contributes 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 being rerouted.
The path cost has a value of 1 to 200000000.
• Default Path Cost — Indicates if the device uses the default path cost. The possible field values are:
– Checked — Device uses the default path cost.
– Unchecked — Device uses path cost defined in the Path Cost field above.
• Priority — Priority value of the LAG. The priority value influences the LAG choice when a bridge has
looped ports. The priority value is between 0-240, in steps of 16.
• Designated Bridge ID — The priority and the MAC Address of the designated bridge.
Configuring Switch Information
337