Cisco 220 Series Smart Plus Administration Manual page 152

Spanning Tree Protocol
Configuring Multiple Spanning Tree
Cisco 220 Series Smart Plus Switches Administration Guide Release 1.0.0.x
• Priority—Enter the port priority for the specified interface and MST
instance.
• Port State—Displays the MSTP status of the specific port on a specific
MSTP instance. The parameters are defined as:
- Disabled—STP is currently disabled.
- Blocking—The port on this instance is currently blocked, and cannot
forward traffic (with the exception of BPDU data) or learn MAC
addresses.
- Learning—The port on this instance is in Learning mode. The port cannot
forward traffic, but it can learn new MAC addresses.
- Forwarding—The port on this instance is in Forwarding mode. The port
can forward traffic and learn new MAC addresses.
• Port Role—Displays the port or LAG role, per port or LAG per instance,
assigned by the MSTP algorithm to provide STP paths:
Master
- —A Master port provides connectivity from an MSTP region to the
outlying CIST root.
- Root—Forwarding packets through this interface provides the lowest
cost path to forward packets to the root device.
- Designated—The interface through which the bridge is connected to the
LAN, that provides the lowest root path cost from the LAN to the Root
Bridge for the MST instance.
- Alternate—The interface provides an alternate path to the root device
from the root interface.
- Backup—The interface provides a backup path to the designated port
path toward the Spanning Tree leaves. Backup ports occur 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—The interface does not participate in the Spanning Tree.
• Mode—Displays the current Spanning Tree mode.
- STP—Classic STP is enabled on the port.
- Rapid STP—Rapid STP is enabled on the port.
- MSTP—MSTP is enabled on the port.
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