To enable CFM to report link events, the link must first be registered with CFM. ERPS acts as a client of CFM and creates the required Management Entity Points (MEPs). For G.8032 v1/v2 implementation:
It is generally recommended to have the CCM interval as short as possible to detect link failures faster, which improves convergence time.
Here is an example:
switch # sh cfm Domain: "erps_6", MD Level: 6 Association: "erps_MA_100", Destination MAC Type: Multicast, VLAN "v2" with 2 cfm ports Transmit Interval: 1000 ms port 27; Down End Point, mepid: 11, transmit-interval: 10000 ms (configured), MEP State: Enabled, CCM Message: Enabled, Send SenderId TLV: Disabled port 37; Down End Point, mepid: 21, transmit-interval: 10000 ms (configured), MEP State: Enabled, CCM Message: Enabled, Send SenderId TLV: Disabled Association: "erps_MA_100", Destination MAC Type: Multicast, VLAN "v2" with 2 cfm ports Transmit Interval: 1000 ms Total Number of Domain : 1 Total Number of Association : 2 Total Number of Up MEP : 0 Total Number of Down MEP : 2 Total Number of MIP : 0 Total Number of Number of CFM port : 4 Total Number of VPLS MIP(Static/Up): 0 / 0
switch # show cfm detail Domain/ Port MP Remote End-Point Remote End-Point MEP Life Flags Association MAC Address IP Address ID time Age ====================================================================================== erps_6 erps_MA_100 27 DE 00:04:96:34:e3:43 0.0.0.0 10 35000 4430 DM 37 DE 00:04:96:27:fb:7b 0.0.0.0 20 35000 2790 DM ====================================================================================== Maintenance Point: (UE) Up End-Point, (DE) Down End-Point Flags: S - Static Entry D - Dynamic Entry CCM Destination MAC: (U) Unicast (M) Multicast NOTE: The Domain and Association names are truncated to 13 characters, Lifetime and Age are in milliseconds. ====================================================================================== Total Number of Dynamic Up RMEP : 0 Total Number of Dynamic Down RMEP : 2 Total Number of Active Static RMEP : 0 Total Number of Inactive Static RMEP : 0
NoteYou must configure a remote MEP-ID for the local MEPs so that a specific association can be maintained between the two ends.
CFM PDU transmit intervals are limited by the supported limits of CFM module. Platforms that do not support CFM in hardware are limited to a minimum interval of 100 ms. The maximum number of down MEPs is limited by the CFM module. This is as low as 32 MEPs in some platforms.