Hi all
I don't think that changing sampling rate to 1 is the solution. sFlow  
by its nature is sampled as you will read here: 
http://www.sflow.org/about/sampling_theory.php

This explains why the figures you see are not 100% accurate. What  I  
could do in ntop is to scale the figures based on sampling rate you  
specify on the switch, but yet this is not a 100% accurate solution

Cheers Luca

On Nov 3, 2008, at 5:26 PM, jr wrote:

> Patrick,
> this is done on the switch, if it supports it.
> My switches (HP ProCurve) won't let me sample any more often than  
> every
> 20st packet :/
> regards,
> johannes
>
> Am Montag, den 03.11.2008, 08:18 -0800 schrieb Patrick Topping:
>> Gerhard,
>>
>> I am suffering from the same issue....  Where did you make the change
>> for this --> I've configured the rate to 1 on all ports.
>>
>> Thanks in advance.
>>
>> -Patrick
>>
>> --------------------------
>>
>>
>> Gerhard Mourani wrote:
>>> Hello Luca,
>>>
>>>> How did you configure sflow in your foundry?
>>> I've configured the rate to 1 on all ports. After doing this, I  
>>> can see
>>> that captured informations are better accurate but not 100%. For
>>> example, if I transfers 100 MB now, I will see around 90 MB. I  
>>> think I
>>> cannot do better than that because it use sampling as you said.
>>>
>>> Gerhard,
>>>
>>> Luca Deri wrote:
>>>
>>>> Gerhard
>>>> sflow uses sampling. hence if you send let's say 100 you will see 1
>>>> using sflow. How did you configure sflow in your foundry?
>>>>
>>>> Luca
>>>>
>>>> On Oct 31, 2008, at 7:33 PM, Gerhard Mourani wrote:
>>>>
>>>>
>>>>
>>>>> Hello List,
>>>>>
>>>>> I've activated the sFlow plugin into my ntop version 3.3.8 to  
>>>>> capture
>>>>> and display sFlow data coming from my "Foundry Network FastIron  
>>>>> Edge
>>>>> 9604" model. If I check inside the plugin page of sFlow about  
>>>>> 'sFlow
>>>>> Interface Statistics' everything are correct and reported data
>>>>> transfers
>>>>> for 'Administrative' or 'Operational' status are ok. But now my
>>>>> problem
>>>>> is when I check inside the ntop web interface and especially about
>>>>> collected data, here the problem is that returned informations  
>>>>> about
>>>>> amount of data are wrong, I mean the amount of data doesn't  
>>>>> correspond
>>>>> to what have really been transfered. So for example if I  
>>>>> transfer 135
>>>>> MBytes I can only see 295.0 KBytes in ntop. Someone know how to  
>>>>> fix
>>>>> this?
>>>>>
>>>>> Thanks for your helps,
>>>>> Gerhard,
>>>>> _______________________________________________
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>>>>>
>>>>>
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