Cabletron Systems STS16-20R Switch User Manual


 
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Monitoring the Network from the Console Statistics Menu SmartStack STS16-20D/STS16-20R Token Ring Switches Installation and User Guide
A CRF that does not connect to other switches or bridges is always forwarding.
When the switch is booted, all CRFs are blocked initially, and then some of
them change to a different state: listening, learning, and forwarding, in that
order. All CRFs that are going to change states from blocking to forwarding
will have done so after two to three times the value of:
Switch Maximum Message Age + (2 x Switch Forward Delay)
DCst (Designated Cost)
Cost for a packet to travel from this CRF to the root in the current spanning tree
configuration. The slower the media, the higher the cost.
Dsg SwId/BrId (Designated Switch Id/Bridge Id)
Priority and ID of the device through which this port has determined it must
communicate with the root of the spanning tree. A BRF will use the base MAC
address + 0x20 for the ID. The first defined CRF will use the base MAC
address + 0x21 for the ID, etc.
Dsg PId (Designated Port Id)
Port on the designated bridge through which this SmartStack STS16-20D/STS16-
20R will communicate with the root of the spanning tree. This information is useful
if the SmartStack STS16-20D/STS16-20R is the designated bridge on one or more
network segments.
# Chgs
Number of topology changes, that is, the number of times the CRF has entered the
forwarding state plus the number of times the CRF has made the transition from
forwarding to blocking. The counter is reset when the switch is reset or the
spanning tree is turned on.
Last Chg
Time since the CRF last entered the forwarding state or made the transition from
forwarding to blocking.
You cannot change any information on this screen. To change the spanning tree
parameters, refer to the section Spanning Tree for BRF Screen on page 99.