STP Port Settings
STP can be set up on a port per port basis.To view the following window click
Configuration > Spanning Tree > STP Port Settings
:
Figure 6- 33. STP Port Settings and MSTP Port Information Table
In addition to setting Spanning Tree parameters for use on the switch level, the Switch allows for the configuration of groups of ports, each port-group of which
will have its own spanning tree, and will require some of its own configuration settings. An STP Group will use the switch-level parameters entered above, with
the addition of
Port Priority
and
Port Cost
.
An STP Group spanning tree works in the same way as the switch-level spanning tree, but the root bridge concept is replaced with a root port concept. A root
port is a port of the group that is elected based on port priority and port cost, to be the connection to the network for the group. Redundant links will be
blocked, just as redundant links are blocked on the switch level.
The STP on the switch level blocks redundant links between switches (and similar network devices).The port level STP will block redundant links within an STP
Group.
It is advisable to define an STP Group to correspond to a VLAN group of ports.
The following fields can be set:
Parameter
Description
Unit
Choose the Switch ID number of the Switch in the switch stack to be modified.
From/To
A consecutive group of ports may be configured starting with the selected port.
External Cost
This defines a metric that indicates the relative cost of forwarding packets to the specified port list. Port cost
can be set automatically or as a metric value.The default value is 0 (auto).
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Allied Telesyn AT-9724TS High-Density Layer 3 Stackable Gigabit Ethernet Switch