Administrator Guide
STP Parameters Default Value
• Port Channel with 40-Gigabit Ethernet
interfaces
• Port Channel with 10-Gigabit Ethernet
interfaces
• 1
Port Priority 8
• 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.
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.
To change the port cost or priority of an interface, use the following commands.
Spanning Tree Protocol (STP) 876