Ethernet Cfm Configuration Guidelines; Configuring The Cfm Domain - Cisco 3845 - Security Bundle Router Software Manual

Chapter 32 Configuring Ethernet OAM, CFM, and E-LMI
When configuring a MEP service, if you do not configure direction, the default is up (inward facing).

Ethernet CFM Configuration Guidelines

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Configuring the CFM Domain

Beginning in privileged EXEC mode, follow these steps to configure the Ethernet CFM domain,
configure a service to connect the domain to a VLAN, or configure a port to act as a MEP. You can also
enter the optional commands to configure other parameters, such as continuity checks.
Command
Step 1
configure terminal
Step 2
ethernet cfm ieee
Step 3
ethernet cfm global
Step 4
ethernet cfm traceroute cache [size entries |
hold-time minutes]
OL-23400-01
CFM is not supported on and cannot be configured on routed ports or on Layer 3 EtherChannels.
CFM is supported on EtherChannel port channels. You can configure an EtherChannel port channel
as MEP or MIP. However, CFM is not supported on individual ports that belong to an EtherChannel
and you cannot add a CFM port to an EtherChannel group.
Port MEP is not supported on Layer 2 EtherChannels, or on ports that belong to an EtherChannel.
You cannot configure CFM on VLAN interfaces or on service instances (bridge domains).
CFM is supported on trunk ports and access ports with these exceptions:
– Trunk ports configured as MEPs must belong to allowed VLANs
– Access ports configured as MEPs must belong to the native VLAN.
A REP port or FlexLink port can also be a service (VLAN) MEP or MIP, but it cannot be a port MEP.
CFM is supported on ports running STP.
You must configure a port MEP at a lower level than any service (VLAN) MEPs on an interface.
You cannot configure tunnel mode by using the native VLAN as the S-VLAN or the C-VLAN.
Do not configure double-tagged 802.1ag CFM packets entering a trunk port.
Purpose
Enter global configuration mode.
Configure the CFM version as IEEE 802.1ag.
Globally enable Ethernet CFM on the switch.
(Optional) Configure the CFM traceroute cache. You can
set a maximum cache size or hold time.
(Optional) For size, enter the cache size in number of
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entry lines. The range is from 1 to 4095; the default is
100 lines.
• (Optional) For hold-time, enter the maximum cache
hold time in minutes. The range is from 1 to 65535; the
default is 100 minutes.
Cisco ME 3800X and 3600X Switch Software Configuration Guide
Configuring Ethernet CFM
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