Spanning Tree Algorithm Configuration

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3
Configuring Interface Settings for MSTP
You can configure the STA interface settings for an MST Instance using the MSTP
Port Configuration and MSTP Trunk Configuration pages.
Field Attributes
The following attributes are read-only and cannot be changed:
STA State – Displays current state of this port within the Spanning Tree.
(See Displaying Interface Settings on page3-100 for additional information.)
-Discarding - Port receives STA configuration messages, but does not forward
packets.
-Learning - Port has transmitted configuration messages for an interval set by
the Forward Delay parameter without receiving contradictory information. Port
address table is cleared, and the port begins learning addresses.
-Forwarding - Port forwards packets, and continues learning addresses.
Trunk – Indicates if a port is a member of a trunk.
(STA Port Configuration only)
The following interface attributes can be configured:
MST Instance ID – Instance identifier to configure. (Range: 0-4094; Default: 0)
Priority – Defines the priority used for this port in the Spanning Tree Protocol. If
the path cost for all ports on a switch are the same, the port with the highest priority
(i.e., lowest value) will be configured as an active link in the Spanning Tree. This
makes a port with higher priority less likely to be blocked if the Spanning Tree
Protocol is detecting network loops. Where more than one port is assigned the
highest priority, the port with lowest numeric identifier will be enabled.
Default: 128
Range: 0-240, in steps of 16
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Eth 1/ 1 information
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Admin status : enable
Role : root
State : forwarding
External path cost : 100000
Internal path cost : 100000
Priority : 128
Designated cost : 200000
Designated port : 128.24
Designated root : 32768.0.0000ABCD0000
Designated bridge : 32768.0.0030F1552000
Fast forwarding : disable
Forward transitions : 1
Admin edge port : enable
Oper edge port : disable
Admin Link type : auto
Oper Link type : point-to-point
Spanning Tree Status : enable
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