When Ethernet ring is configured on two ports located on different IOMs, the SAP queues and virtual schedulers will be created with the actual parameters on each IOM.
Ethernet ring CC messages transmitted over the SAP queues using the default egress QoS policy will use NC (network class) as a forwarding class. If user traffic is assigned to the NC forwarding class, it will compete for the same bandwidth resources with the Ethernet CCMs. Because CCM loss could lead to unnecessary switching of the Ethernet ring, congestion of the queues associated with the NC traffic should be avoided. The operator must configure different QoS policies to avoid congestion for the CCM forwarding class by controlling the amount of traffic assigned into the corresponding queue.
Refer to the 7210 SAS-Mxp, S, Sx, T Services Guide for more information about Ethernet ring applicability in the services solution.