Administration > CFM

Connectivity Fault Management (CFM) is an OAM protocol that includes proactive connectivity monitoring using continuity check messages, fault verification through loop back messages, and fault isolation by examining end-to-end connections between provider edge devices or between customer edge devices.

CFM is implemented as a service level protocol based on service instances which encompass only that portion of the metropolitan area network supporting a specific customer. CFM can also provide controlled management access to a hierarchy of maintenance domains (such as the customer, service provider, and equipment operator).

This switch supports functions for defining the CFM structure, including domains, maintenance associations, and maintenance access points. It also supports fault detection through continuity check messages for all known maintenance points, and cross-check messages which are used to verify a static list of remote maintenance points located on other devices (in the same maintenance association) against those found through continuity check messages. Fault verification is supported using loop back messages, and fault isolation with link trace messages. Fault notification is also provided by SNMP alarms which are automatically generated by maintenance points when connectivity faults or configuration errors are detected in the local maintenance domain.

Configuring Global Settings for CFM

Use the Administration > CFM (Configure Global) page to configure global settings for CFM, such as enabling the CFM process on the switch, setting the start-up delay for cross-check operations, configuring parameters for the link trace cache, and enabling traps for events discovered by continuity check messages or cross-check messages.

Global Parameters

LInk Trace Cache Settings

Continuity Check Errors

Cross-check Errors

Configuring Interfaces for CFM

CFM processes are enabled by default for all physical interfaces, both ports and trunks. You can use the Administration > CFM (Configure Interface) page to change these settings.

Command Usage

Configuring CFM Maintenance Domains

Use the Administration > CFM (Configure MD) pages to create and configure a Maintenance Domain (MD) which defines a portion of the network for which connectivity faults can be managed. Domain access points are set up on the boundary of a domain to provide end-to-end connectivity fault detection, analysis, and recovery. Domains can be configured in a hierarchy to provide management access to the same basic network resources for different user levels.

Command Usage

Configuring General Settings -

Configuring Fault Notification -

Parameters

Creating a Maintenance Domain -

Configuring Detailed Settings for a Maintenance Domain -

Configuring CFM Maintenance Associations

Use the Administration > CFM (Configure MA) pages to create and configure the Maintenance Associations (MA) which define a unique CFM service instance. Each MA can be identified by its parent MD, the MD's maintenance level, the VLAN assigned to the MA, and the set of maintenance end points (MEPs) assigned to it.

Command Usage

Creating a Maintenance Association -

Configuring Detailed Settings for a Maintenance Association

Parameters

Creating a Maintenance Association -

Configuring Detailed Settings for a Maintenance Association

Configuring Maintenance End Points

Use the Administration > CFM (Configure MEP - Add) page to configure Maintenance End Points (MEPs). MEPs, also called Domain Service Access Points (DSAPs), must be configured at the domain boundary to provide management access for each maintenance association.

Command Usage

Parameters

Configuring Remote Maintenance End Points

Use the Administration > CFM (Configure Remote MEP - Add) page to specify remote maintenance end points (MEPs) set on other CFM-enabled devices within a common MA. Remote MEPs can be added to a static list in this manner to verify that each entry has been properly configured and is operational. When cross-checking is enabled, the list of statically configured remote MEPs is compared against the MEPs learned through continuity check messages (CCMs), and any discrepancies reported via SNMP traps.

Command Usage

Parameters

Transmitting Link Trace Messages

Use the Administration > CFM (Transmit Link Trace) page to transmit link trace messages (LTMs). These messages can isolate connectivity faults by tracing the path through a network to the designated target node (i.e., a remote maintenance end point).

Command Usage

Parameters

Transmitting Loop Back Messages

Use the Administration > CFM (Transmit Loopback) page to transmit Loopback Messages (LBMs). These messages can be used to isolate or verify connectivity faults by submitting a request to a target node (i.e., a remote MEP or MIP) to echo the message back to the source.

Command Usage

Parameters

Transmitting Delay-Measure Requests

Use the Administration > CFM (Transmit Delay Measure) page to send periodic delay-measure requests to a specified MEP within a maintenance association.

Command Usage

Parameters

Displaying Local MEPs

Use the Administration > CFM > Show Information (Show Local MEP) page to show information for the MEPs configured on this device.

Displaying Details for Local MEPs

Use the Administration > CFM > Show Information (Show Local MEP Details) page to show detailed CFM information about a local MEP in the continuity check database.

Displaying Local MIPs

Use the Administration > CFM > Show Information (Show Local MIP) page to show the MIPs on this device discovered by the CFM protocol. (For a description of MIPs, refer to the Command Usage section under "Configuring CFM Maintenance Domains.")

Displaying Remote MEPs

Use the Administration > CFM > Show Information (Show Remote MEP) page to show MEPs located on other devices which have been discovered through continuity check messages, or statically configured in the MEP database and verified through cross-check messages.

Displaying Details for Remote MEPs

Use the Administration > CFM > Show Information (Show Remote MEP Details) page to show detailed information for MEPs located on other devices which have been discovered through continuity check messages, or statically configured in the MEP database and verified through cross-check messages.

Displaying the Link Trace Cache

Use the Administration > CFM > Show Information (Show Link Trace Cache) page to show information about link trace operations launched from this device.

Displaying Fault Notification Settings

Use the Administration > CFM > Show Information (Show Fault Notification Generator) page to display configuration settings for the fault notification generator.

Displaying Continuity Check Errors

Use the Administration > CFM > Show Information (Show Continuity Check Error) page to display the CFM continuity check errors logged on this device.