Dell S4048-ON, Configuration Manual

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NOTE: With large configurations (especially those with more ports) Dell Networking recommends increasing the
hello-time.
The range is from 1 to 10.
the default is 2 seconds .
• 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
Spanning Tree Protocol (STP)
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