HP MSR SERIES User Manual

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• Two or more MSTP-enabled devices belong to the same MST region only if they are configured with
the same format selector (0 by default, not configurable), MST region name, VLAN-to-instance
mapping entries in the MST region, and MST region revision level, and they are interconnected
through physical links.
• After specifying the current device as the root bridge or a secondary root bridge, you cannot
change the priority of the device.
• If two or more devices with the same bridge priority have been designated to be root bridges of the
same spanning tree instance, MSTP will select the device with the lowest MAC address as the root
bridge.
• The values of forward delay, hello time, and max age are interdependent. Incorrect settings of these
values might cause network flapping. HP recommends you to set the network diameter and let the
device automatically set an optimal hello time, forward delay, and max age. The settings of hello
time, forward delay and max age must meet the following formulae:
 2 × (forward delay – 1 second) >= max age
 Max age >= 2 × (hello time + 1 second)
• If the device is not enabled with BPDU guard, when an edge port receives a BPDU from another port,
it transits into a non-edge port. To restore its port role as an edge port, you must restart the port.
• Configure ports that are directly connected to terminals as edge ports and enable BPDU guard for
them. In this way, these ports can rapidly transit to the forwarding state, and network security can
be ensured.
Recommended MSTP configuration procedure
Before you configure MSTP, you must determine the role of each device in each MSTI: root bridge or leaf
node. In each MSTI, one, and only one device acts as the root bridge, and all others as leaf nodes.
Follow these steps to configure MSTP:
Ste
p
Remarks
1. Configuring an MST
region.
Optional.
Configure the MST region-related parameters and VLAN-to-instance mappings.
By default, the MST region-related parameters adopt the default values, and all
VLANs in an MST region are mapped to MSTI 0.
2. Configuring MSTP
globally.
Required.
Enable MSTP globally and configure MSTP parameters.
By default, MSTP is disabled globally. All MSTP parameters have default values.
3. Configuring MSTP on
a port.
Optional.
Enable MSTP on a port and configure MSTP parameters.
By default, MSTP is enabled on a port, and all MSTP parameters adopt the
default values.
Configuring an MST region
1. From the navigation tree, select Advanced > MSTP > Region.

HP MSR SERIES Specifications

General

Brand	HP
Model	MSR SERIES
Category	Network Router
Language	English