Only RIB-API MPLS tunnel table entries support ingress statistics. The counters are attached to the ILM entry that is formed when the RIB-API entry is programmed. When different RIB-API entries use the same ILM or label, then the traffic statistics for these RIB-API entries are identical. Traffic counters are kept until the ILM entry is removed. Because of a lack of resources, the system may not be able to allocate counters (statistic indexes) to an ILM. In this case, the system automatically retries until it succeeds.