HP VPN Firewall Appliances Network Management Command Reference

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Syntax
stp [ instance instance-id ] cost cost
undo stp [ instance instance-id ] cost
Default
The device automatically calculates the path costs of ports in each spanning tree based on the
corresponding standard.
Views
Ethernet interface view, Layer 2 aggregate interface view
Default command level
2: System level
Parameters
instance instance-id: Sets the path cost of the ports in a particular MSTI. For the value range for
instance-id, see "instance." 0 represents the CI
ST.
cost: Specifies the path cost of the port, with an effective range that depends on the path cost calculation
standard adopted.
• With the IEEE 802.1d-1998 standard selected for path cost calculation, the cost argument ranges
from 1 to 65535.
• With the IEEE 802.1t standard selected for path cost calculation, the cost argument ranges from 1
to 200000000.
• With the private standard selected for path cost calculation, the cost argument ranges from 1 to
200000.
Usage guidelines
Configured in Ethernet interface view, the setting takes effect only on the interface.
Configured in Layer 2 aggregate interface view, the setting takes effect only on the aggregate interface.
Configured on a member port in an aggregation group, the setting takes effect only after the port leaves
the aggregation group.
To set the path cost of an MSTP port in a specific MSTI, use this command with the MSTI specified. To set
the path cost of an MSTP port in the CIST or an STP or RSTP port, use this command without specifying
any MSTI.
Path cost is an important factor in spanning tree calculation. Setting different path costs for a port in
MSTIs allows different VLAN traffic flows to be forwarded along different physical links and enables
VLAN-based load balancing.
The path cost setting of a port can affect the role selection of the port. When the path cost of a port is
changed, the system re-calculates the role of the port and initiates a state transition.
Examples
# In MSTP mode, set the path cost of port GigabitEthernet 0/3 in MSTI 2 to 200.
<Sysname> system-view
[Sysname] interface gigabitethernet 0/3
[Sysname-GigabitEthernet0/3] stp instance 2 cost 200
Related commands
• display stp