Modify Interface Pvst+ Parameters - Dell Force10 S4810P Configuration Manual

Task
Change the max-age parameter.
Range: 6 to 40
Default: 20 seconds
The values for global PVST+ parameters are given in the output of the command
as shown in

Modify Interface PVST+ Parameters

You can adjust two interface parameters to increase or decrease the probability that a port becomes a
forwarding port:
• Port cost is a value that is based on the interface type. The greater the port cost, the less likely the port
will be selected to be a forwarding port.
• Port priority influences the likelihood that a port will be selected to be a forwarding port in case that
several ports have the same port cost.
Table 38-2
Table 38-2. PVST+ Default Port Cost Values
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
Note: The FTOS implementation of PVST+ uses IEEE 802.1s costs as the default costs. Other
implementations use IEEE 802.1d costs as the default costs if you are using Dell Force10 systems in a
multi-vendor network, verify that the costs are values you intended.
To change the port cost or priority of an interface:
Task
Change the port cost of an interface.
Range: 0 to 200000
Default: see Table
810
| Per-VLAN Spanning Tree Plus (PVST+)
Figure 38-4.
lists the default values for port cost by interface.
38-2.
Command Syntax
vlan max-age
Default Value
200000
20000
2000
180000
18000
1800
Command Syntax
spanning-tree pvst vlan cost
Command Mode
PROTOCOL PVST
,
show spanning-tree pvst
Command Mode
INTERFACE