Advanced Traffic Management Guide K/KA/KB.15.15

Log messageEvent
LLDP unable to assign port port-number to VLAN vlan-id
because spanning-tree is running in RPVST+ mode
LLDP subsystem tries to dynamically
change port VLAN assignments when
mode is RPVST
The number of vPorts on slot slot-number exceeds the
recommended limit of vport-count. PVST BPDUs may be
dropped.
VPORT counts exceed 200
Using RPVST+ debug
While the Event Log records switch-level progress, status, and warning messages on the switch,
the Debug/System Logging (Syslog) feature provides a way to record Event Log and debug messages
on a remote device. For example, you can send messages about routing misconfigurations and
other network protocol details to an external device, and later use them to debug network-level
problems. The Debug/Syslog feature allows you to specify the types of Event Log and debug
messages that you want to send to an external device. The two commands described next affect
debug operation for RPVST+. For further information on debug operation, see the Management
and Configuration Guide for your switch.
Syntax:
spanning-tree clear-debug-counters [ports port-list] [vlan vid-list]
Clears all spanning tree debug counters unless specific ports and/or VLANs are
specified.
ports port-list Clears spanning tree debug counters on the specified
ports.
[ethernet]port-list Clears spanning tree debug counters on an entered
list of posts or all for the ports command
parameter.
vlan Clears spanning tree debug counters for the VLAN.
vlan vlan-id-list One or more identifiers for the VLAN command
parameter.
Using the vlan and ports options together clears the spanning tree debug counters
on the specified port(s) for the specified VLAN(s). Counters maintained on the same
port(s) for other VLAN(s) are not cleared.
Syntax:
[no] debug rpvst [event[filter vlan vid-list]]
[no] debug rpvst [packet[filter port port-list [vlan vid-list]]]
Displays RPVST+ debug messages on the destination device specified with the
debug destination logging | session | buffer command.
event Displays RPVST+ Event Log messages.
filter vlan vid-list Limits log messages to those generated on
the specified VLAN(s).
packet Displays RPVST+ packets sent and received.
filter port port-list [vlan
vid-list]
Limits packets displayed to those generated
on the specified port(s). If the vlan option
is used, then packets displayed are further
limited to the ports on the specified VLAN(s).
The no form of the command disables display of RPVST+ debug messages on the
destination device.
162 Rapid per-VLAN spanning tree (RPVST+) operation