Accton Technology ES3552XA, ES3526XA manual Displaying Interface Settings

Spanning Tree Algorithm Configuration 3

CLI – This example enables Spanning Tree Protocol, sets the mode to MST, and then configures the STA and MSTP parameters.

Console(config)#spanning-tree		4-161
Console(config)#spanning-tree	mode mstp	4-161
Console(config)#spanning-tree	priority 40000	4-164
Console(config)#spanning-tree	hello-time 5	4-163
Console(config)#spanning-tree	max-age 38	4-164
Console(config)#spanning-tree	forward-time 20	4-163
Console(config)#spanning-tree	pathcost method long	4-165
Console(config)#spanning-tree	transmission-limit 4	4-166
Console(config)#spanning-tree	mst-configuration	4-166
Console(config-mstp)#revision	1	4-169
Console(config-mstp)#name R&D		4-168
Console(config-mstp)#max-hops	30	4-169
Console(config-mstp)#

Displaying Interface Settings

The STA Port Information and STA Trunk Information pages display the current status of ports and trunks in the Spanning Tree.

Field Attributes

•Spanning Tree – Shows if STA has been enabled on this interface.

•STA Status – Displays current state of this port within the Spanning Tree:

-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.

The rules defining port status are:

-A port on a network segment with no other STA compliant bridging device is always forwarding.

-If two ports of a switch are connected to the same segment and there is no other STA device attached to this segment, the port with the smaller ID forwards packets and the other is discarding.

-All ports are discarding when the switch is booted, then some of them change state to learning, and then to forwarding.

•Forward Transitions – The number of times this port has transitioned from the Learning state to the Forwarding state.

•Designated Cost – The cost for a packet to travel from this port to the root in the current Spanning Tree configuration. The slower the media, the higher the cost.

•Designated Bridge – The bridge priority and MAC address of the device through which this port must communicate to reach the root of the Spanning Tree.

•Designated Port – The port priority and number of the port on the designated bridging device through which this switch must communicate with the root of the Spanning Tree.

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