Dell Force10 E300, Configuration Manual

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There is a need for Layer 2 equivalents to manage and troubleshoot native Layer 2 Ethernet networks. With
these tools, you can identify, isolate, and repair faults quickly and easily, which reduces operational cost of
running the network. OAM also increases availability and reduces mean time to recovery, which allows for
tighter service level agreements, resulting in increased revenue for the service provider.
In addition to providing end-to-end OAM in native Layer 2 Ethernet Service Provider/Metro networks,
you can also use CFM to manage and troubleshoot any Layer 2 network including enterprise, datacenter,
and cluster networks.
Maintenance Domains
Connectivity Fault Management (CFM) divides a network into hierarchical maintenance domains, as
shown in
Figure 5-1 .
A CFM maintenance domain is a management space on a network that is owned and operated by a single
management entity. The network administrator assigns a unique maintenance level (0 to 7) to each domain
to define the hierarchical relationship between domains. Domains can touch or nest but cannot overlap or
intersect as that would require management by multiple entities.
Figure 5-1. OAM Domains
Maintenance Points
Domains are comprised of logical entities called Maintenance Points. A maintenance point is an interface
demarcation that confines CFM frames to a domain. There are two types of maintenance points:
• Maintenance End Points (MEPs) : a logical entity that marks the end-point of a domain
• Maintenance Intermediate Points (MIPs) : a logical entity configured at a port of a switch that is an
intermediate point of a Maintenance Entity (ME). An ME is a point-to-point relationship between two
MEPs within a single domain. MIPs are internal to a domain, not at the boundary, and respond to CFM
only when triggered by linktrace and loopback messages. MIPs can be configured to snoop Continuity
Check Messages (CCMs) to build a MIP CCM database.
Ethernet Access
MPLS Core MPLS Access
Customer Network
Customer Network
Customer Domain (7)
Provider Domain (6)
Operator Domain (5) Operator Domain (5) Operator Domain (5)
MPLS Domain (4)
Service Provider Network