Specifications

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Cisco MWR 2941 Mobile Wireless Edge Router Software Configuration Guide, Release 12.2(33)MRB
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Chapter 4 Configuring the Cisco MWR 2941 Router Using the CLI
Configuration Sequence
SNMP Traps
The support provided by the Cisco IOS software implementation of CFM traps is Cisco proprietary
information. MEPs generate two types of Simple Network Management Protocol (SNMP) traps,
continuity check (CC) traps and cross-check traps.
CC Traps
• MEP up—Sent when a new MEP is discovered, the status of a remote port changes, or connectivity
from a previously discovered MEP is restored after interruption.
• MEP down—Sent when a timeout or last gasp event occurs.
• Cross-connect—Sent when a service ID does not match the VLAN.
• Loop—Sent when a MEP receives its own CCMs.
• Configuration error—Sent when a MEP receives a continuity check with an overlapping MPID.
Cross-Check Traps
• Service up—Sent when all expected remote MEPs are up in time.
• MEP missing—Sent when an expected MEP is down.
• Unknown MEP—Sent when a CCM is received from an unexpected MEP.
Ethernet CFM and Ethernet OAM Interaction
To understand how CFM and OAM interact, you should understand the following concepts:
• Ethernet Virtual Circuit, page 4-28
• OAM Manager, page 4-28
• CFM over Bridge Domains, page 4-29
Ethernet Virtual Circuit
An EVC as defined by the Metro Ethernet Forum is a port-level point-to-point or
multipoint-to-multipoint Layer 2 circuit. EVC status can be used by a CE device to find an alternative
path to the service provider network or fall back to a backup path over Ethernet or over another
alternative service such as ATM.
Note Release 12.2(33)MRA does not support configuration of EVCs; it can only receive EVC status
information as a CE device.
OAM Manager
The OAM manager is an infrastructure element that streamlines interaction between OAM protocols.
The OAM manager requires two interworking OAM protocols, in this case Ethernet CFM and Ethernet
OAM. Interaction is unidirectional from the OAM manager to the CFM protocol and the only
information exchanged is the user network interface (UNI) port status. Additional port status values
available include
• REMOTE_EE—Remote excessive errors
• LOCAL_EE—Local excessive errors
• TEST—Either remote or local loopback
After CFM receives the port status, it communicates that status across the CFM domain.