Dell S6000 FTOS 9.0(2.0) Configuration Guide for the System - Page 233

Figure 11-2. CoPP solution example Hardware Queue Rate Limiting Q7 1100 PPS Q6 400 PPS OPSF flood CPU at 1100 PPS ICMP fails STP CPU Software Queue CPU Processes (OSPF, LACP, STP, ICMP, etc) Front End Ports Protocol to Queue Classification (Ingress Flow Entries) STP ICMP PING Packets Q5 Q4 No CoPP Rules Q3 Q2 Q1 Q0 Q7 receives STP at 1100 pps due to network storm/loop. The CPU is hit with the entire 1100 pps and the PING attemp fails intermittently. STP ICMP PING Packets Front End Ports Protocol to Queue Classification (Ingress Flow Entries) Hardware Queue Rate Limiting Q7 1100 PPS Q6 400 PPS Q5 Q4 Q3 Q2 Q1 Q0 CoPP Rule Examples Per-Protocol Rate Limiting 100 PPS 50 PPS OSPF 200 PPS BGP 100 PPS STP 100 PPS ICMP 50 PPS CoPP restricts the STP control packet rate to the CPU to 100 pps. PING works reliably. CPU Software Queue CPU Processes (OSPF, LACP, STP, ICMP, etc) STP ICMP PING Configure Control Plane Policing The S4810 can process maximum of 4200 PPS (packets per second). Protocols that share a single queue may experience flaps if one of the protocols receives a high rate of control traffic even though Per Protocol CoPP is applied. This happens because Queue-Based Rate Limiting is applies first.