User Manual

C HAPTER 14 | Basic Administration Protocols
Connectivity Fault Management
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◆ Multiple domains at the same maintenance level cannot have an MA on
the same VLAN (see "Configuring CFM Maintenance Domains" on
page 481).
◆ Before removing an MA, first remove the MEPs assigned to it (see
"Configuring Maintenance End Points" on page 491).
◆ For a detailed description of the MIP types, refer to the Command
Usage section under "Configuring CFM Maintenance Domains" on
page 481.
Configuring Detailed Settings for a Maintenance Association
◆ CCMs are multicast periodically by a MEP in order to discover other
MEPs in the same MA, and to assure connectivity to all other MEPs/MIPs
in the MA.
◆ Each CCM received is checked to verify that the MEP identifier field sent
in the message does not match its own MEP ID, which would indicate a
duplicate MEP or network loop. If these error types are not found, the
CCM is stored in the MEP’s local database until aged out.
◆ If a maintenance point fails to receive three consecutive CCMs from any
other MEP in the same MA, a connectivity failure is registered.
◆ If a maintenance point receives a CCM with an invalid MEPID or MA
level or an MA level lower than its own, a failure is registered which
indicates a configuration error or cross-connect error (i.e., overlapping
MAs).
◆ The interval at which CCMs are issued should be configured to detect
connectivity problems in a timely manner, as dictated by the nature and
size of the MA.
◆ The maintenance of a MIP CCM database by a MIP presents some
difficulty for bridges carrying a large number of Service Instances, and
for whose MEPs are issuing CCMs at a high frequency. For this reason,
slower CCM transmission rates may have to be used.
PARAMETERS
These parameters are displayed:
Creating a Maintenance Association
◆ MD Index – Domain index. (Range: 1-65535)
◆ MA Index – MA identifier. (Range: 0-2147483647)
◆ MA Name – MA name. (Range: 1-44 alphanumeric characters)
Each MA name must be unique within the CFM-managed network.
◆ Primary VLAN – Service VLAN ID. (Range: 1-4093)
This is the VLAN through which all CFM functions are executed for this
MA.