
Chapter 11
| Interface Commands
Cable Diagnostics
– 420 –
Command Usage
◆
Loopback testing can only be performed on a port that is not linked up. The
internal loopback makes it possible to check that an interface is working
properly without having to make any network connections.
◆
When performing an internal loopback test, packets from the specified
interface are looped back into its internal PHY. Outgoing data is looped back to
the receiver without actually being transmitted.
Example
Console#test loop internal interface ethernet 1/1
Internal loopback test: succeeded
Console#
show
cable-diagnostics
This command shows the results of a cable diagnostics test.
Syntax
show cable-diagnostics interface
[
interface
]
interface
ethernet
unit
/
port
unit
- Unit identifier. (Range: 1)
port
- Port number. (ECS4120-28F/28F-I: 21-24,
Other models: 1-24/48)
Command Mode
Privileged Exec
Command Usage
◆
The results include common cable failures, as well as the status and
approximate distance to a fault, or the approximate cable length if no fault is
found.
◆
For link-down ports, the reported distance to a fault is accurate to /- 2
meters. For link-up ports, the accuracy is +/- 10 meters.
◆
Potential conditions which may be listed by the diagnostics include:
■
OK: Correctly terminated pair
■
Open: Open pair, no link partner
■
Short: Shorted pair
■
Not Supported: This message is displayed for any Gigabit Ethernet ports
linked up at a speed lower than 1000 Mbps.
■
Impedance mismatch: Terminating impedance is not in the reference
range.
Содержание ECS4120-28F
Страница 36: ...Contents 36...
Страница 38: ...Figures 38...
Страница 46: ...Section I Getting Started 46...
Страница 70: ...Chapter 1 Initial Switch Configuration Setting the System Clock 70...
Страница 86: ...Chapter 2 Using the Command Line Interface CLI Command Groups 86...
Страница 202: ...Chapter 5 SNMP Commands Additional Trap Commands 202...
Страница 210: ...Chapter 6 Remote Monitoring Commands 210...
Страница 216: ...Chapter 7 Flow Sampling Commands 216...
Страница 278: ...Chapter 8 Authentication Commands PPPoE Intermediate Agent 278...
Страница 360: ...Chapter 9 General Security Measures Port based Traffic Segmentation 360...
Страница 384: ...Chapter 10 Access Control Lists ACL Information 384...
Страница 424: ...Chapter 11 Interface Commands Power Savings 424...
Страница 446: ...Chapter 13 Power over Ethernet Commands 446...
Страница 456: ...Chapter 14 Port Mirroring Commands RSPAN Mirroring Commands 456...
Страница 488: ...Chapter 17 UniDirectional Link Detection Commands 488...
Страница 494: ...Chapter 18 Address Table Commands 494...
Страница 554: ...Chapter 20 ERPS Commands 554...
Страница 620: ...Chapter 22 Class of Service Commands Priority Commands Layer 3 and 4 620...
Страница 638: ...Chapter 23 Quality of Service Commands 638...
Страница 772: ...Chapter 25 LLDP Commands 772...
Страница 814: ...Chapter 26 CFM Commands Delay Measure Operations 814...
Страница 826: ...Chapter 27 OAM Commands 826 1 1 00 12 CF 6A 07 F6 000084 Enabled Disabled Enabled Disabled Console...
Страница 836: ...Chapter 28 Domain Name Service Commands 836...
Страница 848: ...Chapter 29 DHCP Commands DHCP Relay Option 82 848...
Страница 902: ...Section III Appendices 902...
Страница 916: ...Glossary 916...
Страница 926: ...CLI Commands 926...
Страница 937: ......
Страница 938: ...E092017 CS R02...