Troubleshooting MSTP operation
Table 15: Troubleshooting MSTP operation
Problem
Possible cause
Duplicate packets on a
VLAN, or packets not
arriving on a LAN at all.
The allocation of VLANs to MSTIs may not be identical among all switches in a
region.
A switch intended to
operate in a region
does not receive traffic
from other switches in
the region.
An MSTP switch intended for a particular region may not have the same
configuration name or region revision number as the other switches intended for
the same region. The MSTP configuration name (
spanning-tree config-name
command) and MSTP configuration revision number (
spanning-tree config-
revision
command) must be identical on all MSTP switches intended for the
same region.
Another possible cause is that the set of VLANs and VLAN ID-to-MSTI mappings
(
spanning-tree instance vlan
command) configured on the switch may not
match the set of VLANs and VLAN ID-to-MSTI mappings configured on other
switches in the intended region.
BPDU
BPDUs are data messages that are exchanged across the switches within an extended LAN that uses a
spanning tree protocol topology. BPDU packets contain information on ports, addresses, priorities, and
costs.
About BPDU protection
BPDU protection is a security feature designed to protect the active STP topology by preventing spoofed
BPDU packets from entering the STP domain. In a typical implementation, BPDU protection would be
applied to edge ports connected to end user devices that do not run STP. If STP BPDU packets are received
on a protected port, the feature will disable that port and alert the network manager via an SNMP trap as
shown below.
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Aruba 2530 Advanced Traffic Management Guide for
ArubaOS-Switch 16.09