H3C S5120-SI Series, Руководство по эксплуатации

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Configuration procedure
Follow these steps to configure the priority of the current device in a specified MSTI:
To do... Use the command... Remarks
Enter system view
system-view
—
Configure the priority of the
current device in a specified
MSTI
stp
[
instance instance-id
]
priority priority
Optional
32768 by default
z
After specifying the current device as the root bridge or a secondary root bridge, you cannot
change the priority of the device.
z
During root bridge selection, if all devices in a spanning tree have the same priority, the one with
the lowest MAC address will be selected as the root bridge of the spanning tree.
Configuration example
# Set the device priority in MSTI 1 to 4096.
<Sysname> system-view
[Sysname] stp instance 1 priority 4096
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. Thus, devices beyond the reach of the maximum hop can no longer take part in
spanning tree calculation, and thereby the size of the MST region is confined.
All the devices other than the root bridge in the MST region use the maximum hop value set for the root
bridge.
Configuration procedure
Follow these steps to configure the maximum number of hops of the MST region:
To do... Use the command... Remarks
Enter system view
system-view
—
Configure the maximum hops
of the MST region
stp max-hops hops
Optional
20 by default