Specifications

17-8
System Management Software Configuration Guide for Cisco IE 2000U and Connected Grid Switches
Chapter 17 Configuring Ethernet OAM, CFM, and E-LMI
Configuring Ethernet CFM
• CFM is supported on trunk ports, access ports, and 802.1Q tunnel 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.
• You can configure CFM and VLAN translation on the switch at the same time.
• CFM is not supported on private VLAN ports.
• 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.
• An 802.1Q (QinQ) tunnel port can be a CFM up MEP or a port MEP. On a Connected Grid switch,
you can also configure a MEP on a selective QinQ port.
• A QinQ port cannot be a down MEP or a MIP; you can configure the port as a MIP, but it is not active
or visible in traceroute. Port MEP frames received on a QinQ interface are not tunneled and are
processed locally.
• On a QinQ port, ingress draft 1 traffic is tunneled without translation or consideration of CFM
version.
• You cannot configure tunnel mode by using the native VLAN as the S-VLAN or the C-VLAN.
• For port MEP on a QinQ port, do not enter the vlan dot1q tag native global configuration command
to enable tagging on native VLAN frames.
• Do not configure tagged or untagged 802.1ag CFM packets entering an 802.1Q tunnel port.
• Do not configure double-tagged 802.1ag CFM packets entering a trunk port.
Configuring the CFM Domain
Follow this procedure 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.
BEFORE YOU BEGIN
Review the “Information About Ethernet CFM” section on page 17-2 and “Ethernet CFM Configuration
Guidelines” section on page 17-7.
DETAILED STEPS
Note You do not need to enter the ethernet cfm ieee global configuration command to configure the CFM
version as 802.1ag. The CFM version is always 802.1ag and the command is automatically generated
when you enable CFM.
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
ethernet cfm global Globally enable Ethernet CFM on the switch.