Configuring CFM

To configure CFM, create a maintenance domain and assign it a unique MD level. Next, associate MAs with the specified domain and assign MPs within that MA. Optionally, you can configure the transmission interval for the CCMs, destination MAC type for an MA and remote MEPs statically in an MA.

If a MEP fails to receive a CCM before the last advertised TTL value expires, the system logs a message. After the network administrator sees the system log message, he can send a Layer 2 ping and/or a traceroute message to isolate the fault.


Except for ExtremeSwitching X460-G2 series switches, which support hardware-based CFM, CFM does not use ACL; there are no additional ACL entries present for CFM in the show access-list dynamic command output. ExtremeSwitching X460-G2 series switches consume two lookup-stage ACLs in one system slice.

ExtremeXOS 15.5 provides support for transmitting and receiving ITU-T Y.1731 CCMs. The main difference between IEEE 802.1ag and ITU-T Y.1731 CCMs is between the MAID and MEG ID formats in CCMs: