Cisco 500 series Administration Manual page 251

Configuring the Spanning Tree Protocol
Defining MSTP Interface Settings
Cisco 500 Series Stackable Managed Switch Administration Guide
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.
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 established connections to a shared
segment.
Disabled
- —The interface does not participate in the Spanning Tree.
Boundary
- —The port on this instance is a boundary port. It inherits its
state from instance 0 and can be viewed on the
page.
• Mode—Displays the current Spanning Tree mode.
Classic STP
- —Classic STP is enabled on the port.
Rapid STP
- —Rapid STP is enabled on the port.
MSTP
- —MSTP is enabled on the port.
• Type—Displays the MST type of the port.
Boundary
- —A Boundary port attaches MST bridges to a LAN in a remote
region. If the port is a boundary port, it also indicates whether the device
on the other side of the link is working in RSTP or STP mode.
Internal
- —The port is an internal port.
• Designated Bridge ID—Displays the ID number of the bridge that connects
the link or shared LAN to the root.
• Designated Port ID—Displays the Port ID number on the designated bridge
that connects the link or the shared LAN to the root.
• Designated Cost—Displays 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.
• Remaining Hops—Displays the hops remaining to the next destination.
• Forward Transitions—Displays the number of times the port has changed
from the Forwarding state to the Blocking state.
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STP Interface Settings
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