[atlas]P466 - inconsistent readings?

On 2010.11.30. 13:40, Wilfried Woeber, UniVie/ACOnet wrote:
>> Your graphs look fine to me now. Maybe I missed the window of opportunity? :-)
> 
> Maybe :-)
> 
> My point is that the "outage panel" lists a lot of "downs" for yesterday,
> but these periods are not visible in the graphs for that timeframe as grey
> "no data" bars. Given the stability of my ADSL link, I'd rather believe in
> the graphs instead of the list of down-up transitions.
> 
> So, I probably should have asked: which criteria do you select or evaluate
> to declare a probe "down" and then "up" again? :-)

A probe is considered to be "up" if it's connected to our infrastructure and
is sending in measurement data. If it isn't, then it's "down".

If the probe disconnects for some reason, it'll try to get back as soon as
it can. This is recorded as an event in the connection log. However, if the
probe is able to get back quickly and resume measurements, there may not be
gaps at all in the graphs. So, observing some downtime and having continuous
graphs are not mutually exclusive.

> Btw, just to make that clear, this is not a complaint or an attempt to bother
> you excessively. I "simply" try to understand how this stuff works.
> 
> Because I consider this understanding as essential to grok the information in
> the graphs (and to be able to make potential probe-sponsors intersted).

Therefore your questions are perfectly fair, and I hope I or other members
of the team can answer them sufficiently.

Cheers,
Robert


> Cheers,
> Wilfried.