Specifications

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Cisco MWR 2941 Mobile Wireless Edge Router Release 3.5 Software Configuration Guide, Cisco IOS Release 15.1(3)MR
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Chapter 15 Configuring Ethernet OAM, CFM, and E-LMI
Understanding Ethernet CFM
• Understanding E-LMI, page 15-46
• Configuring E-LMI, page 15-46
• Displaying E-LMI Information, page 15-49
• Enabling Ethernet OAM, page 15-49
• Understanding Microwave 1+1 Hot Standby Protocol, page 15-50
• Configuring Microwave 1+1 Hot Standby Protocol, page 15-52
• Configuration Examples, page 15-55
Understanding Ethernet CFM
Ethernet CFM is an end-to-end per-service-instance (per VLAN) Ethernet layer OAM protocol that
includes proactive connectivity monitoring, fault verification, and fault isolation. End-to-end can be
provider-edge-to-provider-edge (PE-to-PE) device or customer-edge-to-customer-edge (CE-to-CE)
device. Ethernet CFM, as specified by IEEE 802.1ag, is the standard for Layer 2 ping, Layer 2
traceroute, and end-to-end connectivity check of the Ethernet network.
These sections contain conceptual information about Ethernet CFM:
• CFM Domain, page 15-2
• Maintenance Associations and Maintenance Points, page 15-3
• CFM Messages, page 15-5
• Crosscheck Function and Static Remote MEPs, page 15-5
• SNMP Traps and Fault Alarms, page 15-5
• Configuration Error List, page 15-6
• CFM Version Interoperability, page 15-6
• IP SLAs Support for CFM, page 15-6
CFM Domain
A CFM maintenance domain is a management space on a network that is owned and operated by a single
entity and defined by a set of ports internal to it, but at its boundary. You assign a unique maintenance
level (from 0 to 7) to define the hierarchical relationship between domains. The larger the domain, the
higher the level. For example, as shown in Figure 15-1, a service-provider domain would be larger than
an operator domain and might have a maintenance level of 6, while the operator domain maintenance
level is 3 or 4.
As shown in Figure 15-2, domains cannot intersect or overlap because that would require management
by more than one entity, which is not allowed. Domains can touch or nest (if the outer domain has a
higher maintenance level than the nested domain). Nesting domains is useful when a service provider
contract with one or more operators to provide Ethernet service. Each operator has its own maintenance
domain and the service provider domain is a superset of the operator domains. Maintenance levels of
nesting domains should be communicated among the administrating organizations. CFM exchanges
messages and performs operations on a per-domain basis.