Hi Peter
changing them on the fly is not supported. Better if you filter the host with 
-f so avoid processing packets at all, instead of discarding egress flows

Yes of there is a DoS, flows exceeding the threshold are dropped, this to avoid 
to DoS also nProbe. What is the algorithm you have in mind exactly?

Regards Luca

> On 21 Feb 2019, at 01:03, Peter Giles <[email protected]> wrote:
> 
> Hi ntop team, I have a couple of nProbe questions for you:
> 
> We had an incident where a badly behaved host increased the number of flow 
> records being generated by nProbe by a factor of 10 and really stressed our 
> downstream processing.  I ended up restarting our nProbe processes with an 
> added --black-list x.x.x.x/32 option to ignore that host.  That led me to 
> wonder, is there any way to dynamically change the blacklist configuration so 
> that in the future I could add a host or network without having to restart 
> nProbe? Doing so without restarting would be preferable since restarting will 
> result in some data loss across all the monitored traffic.  I didn't see 
> anything in the documentation, but thought it would be worth checking here.
> 
> On a related note, I wonder about the --max-num-flows option which limits the 
> number of active flows in the case of DoS, etc. In the event that the maximum 
> number of flows is exceeded, what flows will get discarded?  Any new flows 
> above the limit, or is there a more selective algorithm?
> 
> Thank you!
> Peter
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