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LevelOne GTL-2691 User Manual

Page 487

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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.

P

ARAMETERS

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.