[ntp:questions] SNTP test bench

David L. Mills mills at udel.edu
Wed Jan 30 19:57:50 UTC 2008


Dag-Erling,

The rate violation is caught in the MRU list, which can be retrieved 
using ntpdc and the monlist command. When the number of clients is 
small, the list can be retrieved over the net. When the number of 
clients is larte, like several hundred, there are many UDP packets and 
one or more are usually dropped. The solution at present is to run ntpdc 
on the server machine and pipe the monlist output to a local file.

Each time a KoD is sent a counter is increased by one. Once each second 
the counter is decreased by one. If an offending packet arrives and the 
counter is less than 2, a KoD is sent; otherwise, the packet is dropped 
without further action. There probably should be some triage, but not 
without additional complexity.

Dave

Dag-Erling Smørgrav wrote:

> "David L. Mills" <mills at udel.edu> writes:
> 
>>These configurable features are in the current snapshot, so that can
>>do the same things.
> 
> 
> One question, what is the range of the "monitor" value on a "discard"
> line in ntp.conf?
> 
> My understanding is that if "monitor" is e.g. 10%, it will only send out
> KoD for 10% of offending requests, is that correct?
> 
> DES




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