On Sun, 3 Aug 2025 at 16:40, Tom Beecher via NANOG <nanog@lists.nanog.org> wrote:
When you say 'the control plane receives 100% of the packets', it sort of depends on what you define as the 'control plane'. That's usually defined as 'did the packet get to the RE/RP to process it' There are many scenarios by which this can break :
- Interface buffers may be full - Interface buffers may be drained fast enough - Oversubscription of forwarding complex - Poorly designed QoS - Incorrect config/bugs of control plane policer on internal interface to CP switch - Central CPU (RE, RP, etc) overwhelmed - Internal CP switch malfunctioning
Goot starting point is: RP/0/RSP0/CPU0:leruuter#show lpts pifib hardware police location 0/3/CPU0 | i SNMP SNMP 25 Static 300 300 0 0 01234567 RP/0/RSP0/CPU0:leruuter#show snmp request drop summary NMS Address INQ Encode Duplicate Stack AIPC Overload Timeout Internal Threshold 192.0.2.1 0 0 0 0 0 0 4 0 0 192.0.2.2 0 0 0 0 0 0 2 0 0 Further 'show snmp trace ...' will help. But this gets really tricky, really fast, you really need your account team on your side. -- ++ytti