Configuring the Spanning Tree Protocol
Defining MSTP Interface Settings
Cisco 500 Series Stackable Managed Switch Administration Guide
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Blocking
—The port on this instance is currently blocked, and cannot
forward traffic (with the exception of BPDU data) or learn MAC
addresses.
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Listening
—The port on this instance is in Listening mode. The port cannot
forward traffic, and cannot learn MAC addresses.
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Learning
—The port on this instance is in Learning mode. The port cannot
forward traffic, but it can learn new MAC addresses.
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Forwarding
—The port on this instance is in Forwarding mode. The port
can forward traffic and learn new MAC addresses.
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Boundary
—The port on this instance is a boundary port. It inherits its
state from instance 0 and can be viewed on the
STP Interface Settings
page.
•
Port Role
—Displays the port or LAG role, per port or LAG per instance,
assigned by the MSTP algorithm to provide STP paths:
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Root
—Forwarding packets through this interface provides the lowest
cost path for forwarding packets to the root device.
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Designated
—The interface through which the bridge is connected to the
LAN, which provides the lowest root path cost from the LAN to the Root
Bridge for the MST instance.
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Alternate
—The interface provides an alternate path to the root device
from the root interface.
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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 established connections to a shared
segment.
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Disabled
—The interface does not participate in the Spanning Tree.
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Boundary
—The port on this instance is a boundary port. It inherits its
state from instance 0 and can be viewed on the
STP Interface Settings
page.
•
Mode
—Displays the current Spanning Tree mode.
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Classic STP
—Classic STP is enabled on the port.
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Rapid STP
—Rapid STP is enabled on the port.
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MSTP
—MSTP is enabled on the port.