
Chapter 19
| Spanning Tree Commands
– 508 –
spanning-tree
bpdu-guard
This command shuts down an edge port (i.e., an interface set for fast forwarding) if
it receives a BPDU. Use the
no
form without any keywords to disable this feature, or
with a keyword to restore the default settings.
Syntax
spanning-tree
bpdu-guard
[
auto-recovery
[
interval
interval
]]
no spanning-tree
bpdu-guard
[
auto-recovery
[
interval
]]
auto-recovery
- Automatically re-enables an interface after the specified
interval.
interval
- The time to wait before re-enabling an interface. (Range: 30-86400
seconds)
Default Setting
BPDU Guard: Disabled
Auto-Recovery: Disabled
Auto-Recovery Interval: 300 seconds
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
◆
An edge port should only be connected to end nodes which do not generate
BPDUs. If a BPDU is received on an edge port, this indicates an invalid network
configuration, or that the switch may be under attack by a hacker. If an
interface is shut down by BPDU Guard, it must be manually re-enabled using
the
no
spanning-tree spanning-disabled
command if the auto-recovery
interval is not specified.
◆
BPDU guard can only be configured on an interface if the edge port attribute is
not disabled (that is, if edge port is set to enabled or auto with the
command).
Example
Console(config)#interface ethernet 1/5
Console(config-if)#spanning-tree edge-port
Console(config-if)#spanning-tree bpdu-guard
Console(config-if)#
Related Commands
spanning-tree edge-port (510)
spanning-tree spanning-disabled (518)
Summary of Contents for ECS4120-28F
Page 36: ...Contents 36...
Page 38: ...Figures 38...
Page 46: ...Section I Getting Started 46...
Page 70: ...Chapter 1 Initial Switch Configuration Setting the System Clock 70...
Page 86: ...Chapter 2 Using the Command Line Interface CLI Command Groups 86...
Page 202: ...Chapter 5 SNMP Commands Additional Trap Commands 202...
Page 210: ...Chapter 6 Remote Monitoring Commands 210...
Page 216: ...Chapter 7 Flow Sampling Commands 216...
Page 278: ...Chapter 8 Authentication Commands PPPoE Intermediate Agent 278...
Page 360: ...Chapter 9 General Security Measures Port based Traffic Segmentation 360...
Page 384: ...Chapter 10 Access Control Lists ACL Information 384...
Page 424: ...Chapter 11 Interface Commands Power Savings 424...
Page 446: ...Chapter 13 Power over Ethernet Commands 446...
Page 456: ...Chapter 14 Port Mirroring Commands RSPAN Mirroring Commands 456...
Page 488: ...Chapter 17 UniDirectional Link Detection Commands 488...
Page 494: ...Chapter 18 Address Table Commands 494...
Page 554: ...Chapter 20 ERPS Commands 554...
Page 620: ...Chapter 22 Class of Service Commands Priority Commands Layer 3 and 4 620...
Page 638: ...Chapter 23 Quality of Service Commands 638...
Page 772: ...Chapter 25 LLDP Commands 772...
Page 814: ...Chapter 26 CFM Commands Delay Measure Operations 814...
Page 836: ...Chapter 28 Domain Name Service Commands 836...
Page 848: ...Chapter 29 DHCP Commands DHCP Relay Option 82 848...
Page 902: ...Section III Appendices 902...
Page 916: ...Glossary 916...
Page 926: ...CLI Commands 926...
Page 937: ......
Page 938: ...E092017 CS R02...