User's Manual

Chapter 6 – Configuring Rapid Spanning Tree
Backup
The port is attached to a LAN that is serviced by another port on the bridge. It is
not used but is standing by. If a failure of the port that is currently designated for
the LAN occurs the backup port will become designated for the LAN.
Alternate
The port is attached to a bridge that provides connectivity to the root bridge. It is
not used but is standing by. If a failure of the current root port occurs this port
will become the new root. If there are multiple alternate ports the best candidate
(cost wise) will be elected root.
Cost
The cost of this port. If the Bridge RSTP Parameters Cost Style is set to STP, 100
Mbps ports will contribute a cost of 19 and 10 Mbps ports contribute a cost of
100. If the Cost Style is set to RSTP, 100 Mbps ports will contribute a cost of
200,000 and 10 Mbps ports contribute a cost of 2,000,000. Note that even if the
Cost style is set to RSTP, a port that migrates to STP will have its cost limited to a
maximum of 65535.
RX RSTs
The count of RSTP configuration messages received on this port.
TX RSTs
The count of RSTP configuration messages transmitted on this port.
RX Configs
The count of STP configuration messages received on this port.
TX Configs
The count of STP configuration messages transmitted on this port.
RX Tcns
The count of configuration change notification messages received on this port.
Excessively high or rapidly increasing counts signal network problems.
TX Tcns
The count of configuration messages transmitted on this port.
Designated Root ID
Provided on the root ports of designated bridges, the Bridge Identifier of the
bridge this port is connected to.
RuggedCom
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