e ninja wrote:

Richard,

On the contrary, as I stated below, the 'impact' of BGP scanner (a housekeeping 
task executed by the main processor) on 'system' performance will continue to 
diminish as more platforms become modular (distributed architecture) and/or 
switch packets in hardware (i.e, independent of RP and LC CPU eg in FPGAs)

Nothing in the aforementioned suggests that BGP scanner (a critical process for 
validating the integrity of the BGP table) will EoL anytime soon. Instead, if 
you note the quotes, Drew is concerned with the impact of the CPU consumed by 
BGP scanner on 'system' performance. This concern does not exist on modular 
platforms with distributed packet switching (c12k, hfr etc.) that switch 
packets independent of main RP CPU. Put simply, even if BGP scanner maxes out 
an RP CPU at 100% temporarily on a distributed platform, it will have zero 
effect on packet switching (a la 'system' perf) through the device.

Your thoughts below dwell more on enhancing the mechanism to reduce frequency.
-------------

Yes, but the confusion in (my mind, anyway) is that sometimes when the RP is at 
high CPU utilization forwarding performance is affected. i.e. in the case of a 
DoS attack, although I suppose that the RP being at high CPU utilization is a 
'by-product' of the forwarding hardware punting so much crap to the RP and not 
vice-versa. So when monitoring the CPU for these kinds of events it can be hard 
to tell in a programmatic way whether it's just BGP scanner, or something more 
nefarious like a TTL Expiration attack, or any of the other 700 types of 
DoS/DDoS style attacks which take place these days.

I suppose the real question is, what do you monitor on a modular/distributed 
system in order to gauge the performance, if not the CPU on the Route 
Processor? are there OIDs for the discrete switching/forwarding engines? I know 
at least on the GSR platform each line card has its own CPU/memory statistics 
available, which is at least ??somewhat?? helpful in quickly identifying a 
problem.

-Drew
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