The value of tmnxDot1agCfmMepEthTestEnable specifies whether
ethernet test frames are to be generated on transmission or
processed on reception. If this object is set to 'false',
then tmnxDot1agCfmMepEthTestPattern is undefined.
When this object is set to 'true', tmnxDot1agCfmMepEthTestPattern
is reset to its default value, unless tmnxDot1agCfmMepEthTestPattern
is set to a specific value in the same SNMP PDU.