Gigabit Ethernet Switch Management Guide
Configuring Interface Settings for MSTP
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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 page 22-10 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.
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Eth 1/ 1 information
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 Admin status: enabled
 Role: root
 State: forwarding
 External admin path cost: 10000
 Internal admin path cost: 10000
 External oper path cost: 10000
 Internal oper path cost: 10000
 Priority: 128
 Designated cost: 0
 Designated port: 128.4
 Designated root: 32768.0.0000E8AAAA00
 Designated bridge: 32768.0.0000E8AAAA00
 Fast forwarding: disabled
 Forward transitions: 2
 Admin edge port: disabled
 Oper edge port: disabled
 Admin Link type: auto
 Oper Link type: point-to-point
 Spanning Tree Status: enabled
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