Hierarchical ingress policing (also known as SAP ingress aggregate meter/policer) allows users to specify the amount of traffic admitted into the system per SAP. It also allows the user to share the available bandwidth per SAP among the different FCs of the SAP. For example, the user can allow the packets classified as Internet data to use the entire SAP bandwidth when other FCs do not have traffic.
Hierarchical ingress policing provides an option to configure a SAP aggregate policer/meter per SAP on SAP ingress. The user should configure the PIR rate of the aggregate policer and optionally configure the burst size.
The aggregate policer monitors the traffic on different FCs and determines if the packet has to be forwarded to an identified profile or dropped. The final disposition of the packet is based on the operating rate of the following:
per FC policer
per SAP aggregate policer
For more information about the final color/profile assigned to the packet, see the 7210 SAS-D, Dxp, K 2F1C2T, K 2F6C4T, K 3SFP+ 8C Services Guide, configure service sap ingress aggregate-meter-rate command description.
The trtcm2 (RFC 4115) meter mode is used only on SAP ingress. When the SAP aggregate policer is configured, the per-FC policer can be only configured in ‟trtcm2” mode. The meter modes ‟srtcm” and ‟trtcm1” can be used in the absence of an aggregate meter.
Before using per-SAP aggregate meter/policer, meter resources must be allocated using the config system resource-profile ingress-internal-tcam sap-aggregate-meter command. These resources are shared with ingress ACLs. A change to the number of resources allocated for the SAP aggregate meter requires a reboot of the node to take effect. The amount of resources allocated for this feature determines the number of SAPs that can use the aggregate meter/policer. See the 7210 SAS-D, Dxp, K 2F1C2T, K 2F6C4T, K 3SFP+ 8C Basic System Configuration Guide for more information.