Cisco MDS 9000 Series Command Reference

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Cisco MDS 9000 Family Command Reference
OL-8413-07, Cisco MDS SAN-OS Release 3.x
Chapter 21 S Commands
system health external-loopback
Usage Guidelines Use this command to run this test on demand for the external devices connected to a switch that are part
of a long haul network.
Examples The following example displays an external loopback command for a Fibre Channel interface.
switch# system health external-loopback interface fc 3/1
This will shut the requested interfaces Do you want to continue (y/n)? [n] y
External loopback test on interface fc3/1 was successful.
The following example displays the effect of the force option when implementing a forced loopback.
switch# system health external-loopback interface fc 3/1 force
External loopback test on interface fc3/1 was successful.
Related Commands Command Description
system health Configures Online Health Management System (OHMS) features for a
specified interface or for the entire switch.
system health
internal-loopback
Explicitly runs an internal OHMS loopback test on demand for a specified
interface or module.
system health
serdes-loopback
Explicitly runs an internal OHMS Serializer/Deserializer (Serdes) loopback
test on demand for a Fibre Channel interface.

Cisco MDS 9000 Series Specifications

General

Category	Switch
Operating System	Cisco NX-OS
Ports	Varies by model
Protocols	Fibre Channel (FC), Fibre Channel over IP (FCIP), iSCSI
Redundancy	Redundant supervisors, power supplies, and fans
Management	Cisco Data Center Network Manager (DCNM), CLI, SNMP
Virtualization Support	VSANs (Virtual SANs)
Security Features	Fibre Channel Security Protocol (FC-SP)
Hot Swappable Components	power supplies, fans
Power Supply Options	AC and DC options available