Cisco Catalyst 4500 Series System Message Guide

2-99
Catalyst 4500 Series Switch Cisco IOS System Message Guide
OL-13091-01
Chapter 2 Messages and Recovery Procedures
SPANTREE Messages
Error Message SPANTREE-2-RECV_PVID_ERR: Received BPDU with inconsistent peer vlan id
[dec] on [char] [char]
Explanation
The listed interface received an SSTP BPDU that is tagged with a VLAN ID that does
not match the VLAN ID on which the BPDU was received. This condition occurs when the native
VLAN is not consistently configured on both ends of an 802.1Q trunk. [dec] is the VLAN ID. The
interface ID is [char].
Recommended Action Verify that the configuration of the native VLAN ID is consistent on the
interfaces on each end of the 802.1Q trunk connection. Once the configuration is consistent,
spanning tree automatically unblocks the interfaces.
Error Message SPANTREE-2-ROOTGUARD_BLOCK: Root guard blocking port [char] on [char].
Explanation
A BPDU was received on the listed interface that advertised a spanning tree root bridge
that was superior to the one already in use. The interface is put into a blocking state and marked as
root guard inconsistent to prevent a suboptimal spanning tree topology from forming.
Recommended Action Enter the show spanning-tree inconsistentports command to review the list
of interfaces with root guard inconsistencies. Determine why devices that are connected to the listed
ports are sending BPDUs with a superior root bridge, and then take action to prevent further
occurrences. Once the invalid BPDUs have been stopped, the interfaces automatically recover and
resume normal operation. By looking at the configuration, ensure that it is appropriate to enable root
guard on the interface.
Error Message SPANTREE-2-ROOTGUARD_CONFIG_CHANGE: Root guard [char] on port [char].
Explanation
There was a change in the spanning tree root guard configuration for the listed interface.
If root guard is enabled, any BPDU that is received on the interface that advertises a superior
spanning tree root bridge to the one that is already in use will cause the interface to be put into
blocking state and marked as root guard inconsistent.
Recommended Action Verify that this is the correct configuration for the listed interface. If this is not
the correct configuration, change the configuration to one that is appropriate for the interface.
Error Message SPANTREE-2-ROOTGUARD_UNBLOCK:Root guard unblocking port [char] on
[char].
Explanation
The listed interface is no longer receiving BPDUs that are advertising a superior root
bridge. The root guard inconsistency is cleared for the interface and then is taken out of the blocking
state if appropriate.
Recommended Action This is an informational message only. No action is required.

Cisco Catalyst 4500 Series Specifications

General

Series	Catalyst 4500 Series
Category	Switch
Layer Support	Layer 2, Layer 3
Form Factor	Modular chassis
Stackable	No
Chassis Slots	3, 6, 7, 10
Power Supply Options	AC, DC
Redundancy	Power supply, Supervisor engine
Network Management	Cisco IOS Software CLI, SNMP, Cisco Prime Infrastructure
Features	Security, QoS
Port Density	Up to 384 ports per chassis
Security Features	802.1X, ACLs, DHCP Snooping, Dynamic ARP Inspection, IP Source Guard
Supervisor Engine	8-E