Cisco Systems A9014CFD manual Understanding the Ethernet OAM Protocol, 10-32

Chapter 10 Configuring Ethernet OAM

LCK Expiry Threshold: 3.5

Level to transmit LCK: Default

Defect Condition: No Defect

presentRDI: FALSE

AIS-Status: Enabled

AIS Period: 60000(ms)

AIS Expiry Threshold: 3.5

Level to transmit AIS: Default

Suppress Alarm configuration: Enabled

Suppressing Alarms: No

MIP Settings:

-------------

Local MIPs:

*= MIP Manually Configured

------------------------------------------------------------------------------

Level PortMacAddress SrvcInst Type Id

------------------------------------------------------------------------------

*5 Gi0/3 0021.d7ef.0700 N/A Vlan 2,7

This is an example of output from the show ethernet cfm traceroute command:

Router# show ethernet cfm traceroute

Current Cache-size: 0 Hops

Max Cache-size: 100 Hops

Hold-time: 100 Minutes

Use the commands in Table 10-3in the privileged EXEC mode to display IP SLA ethernet CFM information.

Table 10-3 Displaying IP SLA CFM Information

Command	Purpose
show ip sla configuration [entry-number]	Displays configuration values including all defaults for all IP SLA
	operations or a specific operation.
show ip sla ethernet-monitor configuration	Displays the configuration of the IP SLA automatic ethernet operation.
[entry-number]
show ip sla statistics [entry-number	Display current or aggregated operational status and statistics.
aggregated details]

Understanding the Ethernet OAM Protocol

The Ethernet OAM protocol for installing, monitoring, and troubleshooting Metro Ethernet networks and Ethernet WANs relies on an optional sublayer in the data link layer of the OSI model. Normal link operation does not require Ethernet OAM. You can implement Ethernet OAM on any full-duplex point-to-point or emulated point-to-point Ethernet link for a network or part of a network (specified interfaces).

OAM frames, called OAM protocol data units (OAM PDUs) use the slow protocol destination MAC address 0180.c200.0002. They are intercepted by the MAC sublayer and cannot propagate beyond a single hop within an Ethernet network. Ethernet OAM is a relatively slow protocol, with a maximum transmission rate of 10 frames per second, resulting in minor impact to normal operations. However, when you enable link monitoring, because the CPU must poll error counters frequently, the number of required CPU cycles is proportional to the number of interfaces that must be polled.

	Cisco ASR 901 Series Aggregation Services Router Software Configuration Guide
10-32	OL-23826-09