Spanning Tree Mst Port Configuration - Ubiquiti EdgeSwitch ES-24-250W Administration Manual

EdgeSwitch Administration Guide
™

Spanning Tree MST Port Configuration

Use the Spanning Tree MST Port Summary page to view and configure the Multiple Spanning Tree (MST)
settings for each interface on the device. To configure MST settings for an interface and to view additional
information about the interface's role in the MST topology, first select the appropriate MST instance from the
MST ID menu. Then, select the interface to view or configure and click Edit.
To display the Spanning Tree MST Port Summary page, click Switching > Spanning Tree > MST Port in the
navigation menu.
Note: If no MST instances have been configured on the switch, the page displays a "No MSTs Available"
message and does not display the fields shown in the illustration below.
Field
MST ID
Interface
Port Role
Port Forwarding State
Port Priority
Port Path Cost
Ubiquiti Networks, Inc.
Spanning Tree MST Port Summary
Spanning Tree MST Port Summary Fields
Description
The menu contains the ID of each MST instance that has been created on the device.
The port or link aggregation group (LAG) associated with the rest of the data in the row. When
configuring MST settings for an interface, this field identifies the interface being configured.
The role of the port within the MST, which is one of the following:
• Root A port on the non-root bridge that has the least-cost path to the root bridge.
• Designated A port that has the least-cost path to the root bridge on its segment.
Alternate
• A blocked port that has an alternate path to the root bridge.
• Backup A blocked port that has a redundant path to the same network segment as another port
on the bridge.
• Master The port on a bridge within an MST instance that links the MST instance to other STP
regions.
• Disabled The port is administratively disabled and is not part of the spanning tree.
• Blocking The port discards user traffic and receives, but does not send, BPDUs. During the
election process, all ports are in the blocking state. The port is blocked to prevent network loops.
• Listening The port sends and receives BPDUs and evaluates information to provide a loop-free
topology. This state occurs during network convergence and is the first state in transitioning to the
forwarding state.
• Learning The port learns the MAC addresses of frames it receives and begins to populate the
MAC address table. This state occurs during network convergence and is the second state in
transitioning to the forwarding state.
• Forwarding The port sends and receives user traffic.
• Disabled The port is administratively disabled and is not part of the spanning tree.
The priority for the port within the MSTI. This value is used in determining which port on a switch
becomes the root port when two ports have the same least-cost path to the root. The port with the
lower priority value becomes the root port. If the priority values are the same, the port with the lower
interface index becomes the root port.
The path cost from the port to the root bridge.
Configuring Switching Information
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