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12-27

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 12-13 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 conf igured:
•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