HP 5500 Ei 5500 Si Switch Series Configuration Guide

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•  You can configure the current device as the root bridge by setting the device priority to 0. For the 
device priority configuration, see  Configuring the device priority. 
Configuring the current device as the root bridge of a specific 
spanning tree 
To configure the current device as the root bridge of a specific spanning tree:  
Step Command Remarks 
1.  Enter system view. 
system-view  N/A 
2.  Configure the current device 
as the root bridge. 
• In STP/RSTP mode: 
stp root primary 
• In PVST...

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Step Command Remarks 
1.  Enter system view. 
system-view  N/A 
2.  Configure the priority of 
the current device. 
• In STP/RSTP mode: 
stp priority  priority 
• In PVST mode: 
stp vlan  vlan-list  priority  priority  
• In MSTP mode: 
stp  [ instance  instance-id  ] priority priority Use one of the commands.
 
The default setting is 
32768. 
 
Configuring the maximum hops of an MST region 
By setting the maximum hops of an MST region, you can restrict the region size. The maximum hops...

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Step Command Remarks 
2.  Configure the network 
diameter of the switched 
network. • In STP/RSTP/MSTP mode: 
stp bridge-diameter  diameter  
• In PVST mode: 
stp vlan  vlan-list  bridge-diameter  diameter  Use one of the 
commands. 
The default setting is 7. 
 
 
NOTE: 
•  In STP/RSTP/MSTP mode, each MST region is considered as a device and the configured network 
diameter is effective only for the CIST (or the common root bridge), but not for MSTIs. 
•   In PVST mode, the network diameter...

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•  An appropriate hello time setting enables the device to quickly detect link failures on the network 
without using excessive network resources. If the  hello time is too long, the device will mistake 
packet loss as a link failure and trigger a new spanni ng tree calculation process. If the hello time is 
too short, the device will frequently send the same configuration BPDUs, which adds the device 
burden and wastes network resources. HP recommends you to use the default setting. 
•   If the max...

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Step Command Remarks 
2.  Configure the timeout factor of the 
device.   stp timer-factor 
factor  3 by default.
 
 
Configuring the maximum port rate 
Th e  m a xi mu m  ra t e  o f  a  p o r t  re fe r s  t o  t h e  m a xi m u m  nu m b e r  o f  B PD Us  t h e  p o r t  c a n  s e n d  wi t h i n  e a ch  h e l l o  
time. The maximum rate of a port is related to the ph ysical status of the port and the network structure. 
The higher the maximum port rate is, the more BPDUs  will be sent within...

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Step Command Remarks 
1.  Enter system view. 
system-view  N/A 
2.  Enter interface view or port 
group view. 
• Enter Layer 2 Ethernet interface view or 
Layer 2 aggregate interface view: 
interface interface-type 
interface-number  
• Enter port group view: 
port-group manual  port-group-name Use one of the commands.
3.
  Configure the current ports as 
edge ports.   stp 
edged-port enable   All ports are non-edge ports 
by default.
 
 
Configuring path costs of ports 
Path cost is a parameter...

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Link speed  Port type Path cost 
IEEE 802.1d-1998 IEEE 802.1t  Private standard  
Aggregate interface 
containing 4 Selected ports
 500,000 1400 
100 Mbps Single port 
19 200,000 200 
Aggregate interface 
containing 2 Selected ports
 100,000 180 
Aggregate interface 
containing 3 Selected ports
 66,666 160 
Aggregate interface 
containing 4 Selected ports
 50,000 140 
1000 Mbps 
Single port 
4 20,000 20 
Aggregate interface 
containing 2 Selected ports
 10,000 18 
Aggregate interface 
containing 3...

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Step Command Remarks 
2.  Specify a standard for the 
device to use when it 
calculates the default path 
costs of its ports.  stp pathcost-standard
 
{  dot1d-1998  | dot1t  | legacy  }  Optional. 
legacy by default.
 
 
Configuring path costs of ports 
When the path cost of a port changes, the system re-c alculates the role of the port and initiates a state 
transition.  
To configure the path cost of ports: 
 
Step Command Remarks 
1.   Enter system view. 
system-view  N/A 
2.  Enter interface...

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Configuring the port priority 
When the priority of a port changes, MSTP re-calculates the role of the port and initiates a state transition. 
The priority of a port is an important factor in de termining whether the port can be elected as the root 
port of a device. If all other conditions are the same, the port with the highest priority will be elected as 
the root port. 
On a spanning tree device, a port can have different priorities and play different roles in different 
spanning trees, so that...

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Step Command Remarks 
1.  Enter system view. 
system-view  N/A 
2.  Enter interface view or 
port group view. 
• Enter Layer 2 Ethernet interface view or Layer 
2 aggregate interface view: 
interface interface-type interface-number  
• Enter port group view: 
port-group manual  port-group-name Use one of the 
commands.
 
3.  Configure the port link 
type.   stp point-to-point 
{ auto  | force-false  | 
force-true  }  By default, the link type is 
auto
 where the port 
automatically detects the 
link...