Example: Configuring Ethernet CFM on Physical Interfaces
CFM can be used to monitor the physical link between two routers. This functionality is similar to that supported by theIEEE 802.3ah LFM protocol.
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Note: The configurations in this example are only partial examples of complete and functional router configurations. Do not copy these configurations and use them directly on an actual system. |
In the following example, two routers (Router 1 and Router 2) are connected by a point-to-point Gigabit Ethernet link. The link between these two routers is monitored using CFM. This is shown in Figure 1. The single boundary is a “down mep” in CFM terminology.
Figure 1: Ethernet CFM on Physical Interfaces

Router 1
Configure the interface and CFM:
- [edit]
- interfaces ge-1/0/1 {
-
- unit 0 {
- family inet;
- }
- }
- protocols {
-
- oam {
-
- ethernet {
-
- connectivity-fault-management {
-
- maintenance-domain private {
- level 0;
-
- maintenance-association private-ma {
-
- continuity-check {
- interval 1s;
- }
-
- mep 100 {
- interface ge-1/0/1;
- direction down;
- auto-discovery;
- }
- }
- }
- }
- }
- }
- }
The configuration on Router 2 mirrors that on Router 1.
Router 2
Configure the interface and CFM:
- [edit]
- interfaces ge-0/2/5 {
-
- unit 0 {
- family inet;
- }
- }
- protocols {
-
- oam {
-
- ethernet {
-
- connectivity-fault-management {
-
- maintenance-domain private {
- level 0;
-
- maintenance-association private-ma {
-
- continuity-check {
- interval 1s;
- }
-
- mep 100 {
- interface ge-0/2/5;
- direction down;
- auto-discovery;
- }
- }
- }
- }
- }
- }
- }


