Alcatel Carrier Internetworking Solutions Omni Switch/Router - Manual (Page 481)

Configuring Spanning Tree
Page 17-33
Field Descriptions
The following section explains the fields displayed by the stps command.
Slot/Intf . The slot and interface (port) number of the port.
Service/Inst . The service type and instance of the service connected to the port.
Pri. The value (from 0 to 256) of the priority of the port, 0 being the highest priority.
State. The port's current state as defined by application of the spanning tree protocol. This
state controls what action a port takes on reception of a frame. The State values are:
Disabled This port has been disabled.
Blocking This port is not participating in transmitting data to prevent loops.
Listening This port is preparing to transmit data, but is temporarily disabled to
prevent loops.
Learning This port is preparing to transmit data, but is temporarily disabled to
prevent loops. This is different from Listening in that the port is acquir-
ing data to facilitate data transmission.
Forwarding This port is transmitting data.
Some of these values are not available if you are using IBM Spanning Tree. For information
on the differences between IEEE and IBM Spanning Tree, see Configuring Spanning Tree
Parameters on page 17-25.
Path Cost. The contribution of this port to the path cost towards the spanning tree root. The
spanning tree root will include this port.
Desig Cost. The path cost to the designated port of the segment connected to this port. If this
is the root bridge this value is 0.
Des Port . The unique port identifier of the bridge port believed to be the designated port for
the LAN associated with the port.
Rt Pt. This field indicates if this port is the root port. The root port is the port that offers the
lowest cost path to the root bridge.
Swt Pt. This field indicates if this port is in Optimized Switch Mode. Optimized Switch Mode is
appropriate for dedicated connections to a single workstation or server. For more informa-
tion, see Chapter 19, “Managing Groups and Ports.”
FWD Transition. The number of times this port has changed from the Learning state to the
Forwarding state.
Root Bridge ID. The bridge identification number of the root bridge.
Desig Bridge ID. The unique bridge identifier of the designated bridge for this port (LAN).