Dell S3048-ON, Руководство по настройке

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• Change the
max-age
parameter (the refresh interval for configuration information that is generated by recomputing the spanning tree
topology).
PROTOCOL SPANNING TREE mode
max-age seconds
The range is from 6 to 40.
The default is 20 seconds .
To view the current values for global parameters, use the
show spanning-tree 0
command from EXEC privilege mode. Refer to the
second example in Enabling Spanning Tree Protocol Globally .
Modifying Interface STP Parameters
You can set the port cost and port priority values of interfaces in Layer 2 mode.
• Port cost — a value that is based on the interface type. The greater the port cost, the less likely the port is selected to be a forwarding
port.
• Port priority — influences the likelihood that a port is selected to be a forwarding port in case that several ports have the same port
cost.
The default values are listed in Modifying Global Parameters .
To change the port cost or priority of an interface, use the following commands.
• Change the port cost of an interface.
INTERFACE mode
spanning-tree 0 cost cost
The range is from 0 to 65535.
The default values are listed in Modifying Global Parameters .
• Change the port priority of an interface.
INTERFACE mode
spanning-tree 0 priority priority-value
The range is from 0 to 15.
The default is 8 .
To view the current values for interface parameters, use the
show spanning-tree 0
command from EXEC privilege mode. Refer to
the second example in Enabling Spanning Tree Protocol Globally .
Enabling PortFast
The PortFast feature enables interfaces to begin forwarding traffic approximately 30 seconds sooner.
Interfaces forward frames by default until they receive a BPDU that indicates that they should behave otherwise; they do not go through
the Learning and Listening states. The
bpduguard shutdown-on-violation option causes the interface hardware to be shut down
when it receives a BPDU. When you only implement
bpduguard
, although the interface is placed in an Error Disabled state when receiving
the BPDU, the physical interface remains up and spanning-tree drops packets in the hardware after a BPDU violation. BPDUs are dropped
in the software after receiving the BPDU violation.
CAUTION: Enable PortFast only on links connecting to an end station. PortFast can cause loops if it is enabled on an interface
connected to a network.
To enable PortFast on an interface, use the following command.
830 Spanning Tree Protocol (STP)