Configuring the switch
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Switch Spanning Tree Group Port Configuration
To display the following form, go to the Switch Spanning Tree Group Configuration form. Select a Switch
Port number.
Spanning Tree port parameters are used to modify STP operation on an individual port basis.
By default for STP/PVST+, Spanning Tree is turned Off for downlink ports (1-16), and turned On for the
cross-connect port (17) and uplink ports (19-25). By default for RSTP/MSTP, Spanning Tree is turned On
for all ports, with downlink ports configured as Edge ports.
The following table describes the Switch Spanning Tree Group Port Configuration controls:
Table 118
Switch Spanning Tree Group Port Configuration controls
Control Description
Port Priority (0-255)
Configures the port priority. The port priority helps determine which bridge
port becomes the designated port. In a network topology that has multiple
bridge ports connected to a single segment, the port with the lowest port
priority becomes the designated port for the segment. The range is 0 to 255,
and the default is 128.
RSTP/MSTP: The range is 0 to 240, in steps of 16 (0, 16, 32...) and the
default is 128.
Port Path Cost
Configures the port path cost. The port path cost is used to help determine
the designated port for a segment. Generally speaking, the faster the port,
the lower the path cost. The range is 1 to 65535.
The range is 1 to 65535. The default is 100 for 10Mb ports,
10 for 100 Mb ports, 4 for Gigabit ports, and 2 for 10Gb ports.
A value of 0 indicates that the default cost will be computed for an auto-
negotiated link speed.
RSTP/MSTP: The range is 1 – 200000000, and the default it 20000 for
Gigabit ports, 2000 for 10Gb ports.
