Need help to configure CFM

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I need some advice on the best way to configure CFM.

 I have several EAPS rings with some VMANs configured and operational. The customers sometimes complain about packet loss, I would like to configure CFM in a way that I can monitor the packet loss end-to-end for each VMAN and collect this information via SNMP, as well as the information about the status of the VMANs end-to-end (up/down).

I already read all the documentation possible, understood all the concepts of UP MEPs, DOWN MEPs, etc. But in the labs that I did I had some problems (i.e. the CFM group was always down).

If someone could point me in the right direction, give me some simple example and how to get to OID to monitor CFM via SNMP I would appreciate it. The example in the concepts guide doesn't include CFM groups and CFM segments, and doesn't make it clear as how to configure CFM in a ring topology.
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Posted 2 years ago

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Prashanth KG, Employee

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Hi Thiago,

Please share the switch details in which you have tried to configure CFM in the lab. Some platforms do not support dymanic MEP learning. 

Please refer the article below for reference:

We will try to get you the answers for the other queries.
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Hello Prashanth,

In my tests I was using the  EXOS VMs, but I also configured it in a production environment which is composed of a Mixture of BD8800, X460, X450 and X250, for this particular test I used the BD and the X460.

I read in the documentation that the X460 doesn't support dynamic MEP learning, but the thing is that even with the MAC configured statically the CFM group still doesn't go up.

Consider the following environment:

                          (p3)                                            (p3)
                             |                                                 |

Switches sw4, sw2 and sw3 make a ring for the backbone, while switches sw1 and sw5 are the customers. Imagine a transport VMAN configured in the backbone, called VMAN423. As well as a inner customer VLAN, called VLAN15 that interconnects sw1 and sw5.

What I want is to monitor the VMAN423 via CFM and collect the information via SNMP.

I configured a CFM domain with md-level 5. I configured UP MEPs (SW4-p2 and SW3-p1) and MIPS (SW4-p1,SW4-p3,SW2-p3,SW2-p2,SW3-p2 and SW3-p3).

I also configured two CFM domains with md-level 4, one with DOWN MEPs (SW4-p1 and SW3-p2) and the other with DOWN MEPs (SW4-p3 and SW3-p3). The first one also have MIPs in SW2 accordingly.

The CFM group is always down, I configured the RMEP MAC address statically. If someone could give me an example on how to do this, as well as the MIB for monitoring the CFM segments and the CFM groups.