Configuring the maximum hops of an mst region – H3C Technologies H3C S12500 Series Switches User Manual
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the priority of a switch to a low value to specify the switch as the root bridge of the spanning tree. A
spanning tree switch can have different priorities in different MSTIs.
To configure the priority of a switch in a specified MSTI:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Configure the priority of the
switch.
•
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 any command.
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
configured on the regional root bridge will be used as the maximum hops of the MST region.
The regional root bridge always sends a configuration BPDU with a hop count set to the maximum value.
When a switch receives this configuration BPDU, it decrements the hop count by 1 and uses the new hop
count in the BPDUs it propagates. When the hop count of a BPDU reaches 0, it is discarded by the device
that received it. This prevents devices beyond the reach of the maximum hop from taking part in spanning
tree calculation, which limits the size of the MST region.
Make this configuration on the root bridge only. All other devices in the MST region use the maximum
hop value set for the root bridge.
To configure the maximum number of hops of an MST region:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Configure the maximum hops
of the MST region.
stp max-hops hops
The default setting is 20.
Configuring the network diameter of a switched
network
Any two terminal devices in a switched network are interconnected through a specific path composed of
a series of devices. The network diameter is the number of devices on the path composed of the most
devices. The network diameter is a parameter that indicates the network size. A bigger network diameter
indicates a larger network size. Based on the network diameter you configured, the system automatically
sets an optimal hello time, forward delay, and max age for the switch.
To configure the network diameter of a switched network: