Modifying Global Parameters - Dell S4820T Configuration Manual

INTERFACE mode
spanning-tree 0

Modifying Global Parameters

You can modify the spanning tree parameters. The root bridge sets the values for forward-delay, hello-
time, and max-age and overwrites the values set on other bridges participating in STP.
NOTE: Dell Networking recommends that only experienced network administrators change the
spanning tree parameters. Poorly planned modification of the spanning tree parameters can
negatively affect network performance.
The following table displays the default values for STP.
Table 81. STP Default Values
STP Parameters
Forward Delay
Hello Time
Max Age
Port Cost
• 100-Mb/s Ethernet interfaces
• 1-Gigabit Ethernet interfaces
• 10-Gigabit Ethernet interfaces
• Port Channel with 100 Mb/s Ethernet interfaces
• Port Channel with 1-Gigabit Ethernet interfaces
• Port Channel with 10-Gigabit Ethernet
interfaces
Port Priority
• Change the forward-delay parameter (the wait time before the interface enters the Forwarding
state).
PROTOCOL SPANNING TREE mode
forward-delay seconds
The range is from 4 to 30.
The default is 15 seconds.
• Change the hello-time parameter (the BPDU transmission interval).
PROTOCOL SPANNING TREE mode
hello-time seconds
NOTE: With large configurations (especially those with more ports) Dell Networking
recommends increasing the hello-time.
The range is from 1 to 10.
988
Default Value
15 seconds
2 seconds
20 seconds
• 19
• 4
• 2
• 18
• 3
• 1
8
Spanning Tree Protocol (STP)