
Chapter 16
| Loopback Detection Commands
– 476 –
loopback-detection
This command enables loopback detection globally on the switch or on a specified
interface. Use the
no
form to disable loopback detection.
Syntax
[
no
]
loopback-detection
Default Setting
Disabled
Command Mode
Global Configuration
Interface Configuration (Ethernet, Port Channel)
Command Usage
Loopback detection must be enabled globally for the switch by this command and
enabled for a specific interface for this function to take effect.
Example
This example enables general loopback detection on the switch, disables loopback
detection provided for the spanning tree protocol on port 1, and then enables
general loopback detection for that port.
Console(config)#loopback-detection
Console(config)#interface ethernet 1/1
Console(config-if)#no spanning-tree loopback-detection
Console(config-if)#loopback-detection
Console(config)#
loopback-detection
action
This command specifies the protective action the switch takes when a loopback
condition is detected. Use the no form to restore the default setting. Use the
no
form to restore the default setting.
Syntax
loopback-detection action
{
block
|
none
|
shutdown
}
no loopback-detection action
block
- When a loopback is detected on a port which a member of a
specific VLAN, packets belonging to that VLAN are dropped at the
offending port.
none
- No action is taken.
shutdown
- Shuts down the interface.
Default Setting
Shut down
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...