Справочник Пользователя для Digital Networks North America DNswitch 800

22  Configuring and Monitoring the Switch

DNswitch 800

The parameters shown in the following figure and table are for port STA 
Information (Port 1-8). 

Port Status

Displays the current state of this port within the spanning tree:

No Link

There is no valid link on the port.

Disabled

Port has been disabled by the user or has failed 

diagnostics.

Blocked

Port receives STA configuration messages, but 

does not forward packets.

Listening

Port will leave blocking state due to topology 

change, starts transmitting configuration 
messages, but does not yet forward packets.

Learning

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 The 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 blocked.

• All ports are blocked when the switch is booted, 

then some of them change state to listening, to 
learning, and then to forwarding. 

Forward Transitions

The number of times the port has changed status to 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.