perfsonar development work

[Andreas Hanemann <>]

I have added this point to the collection of potential issues on the
meeting page.
http://wiki.perfsonar.net/jra1-wiki/index.php/070430-perfSONAR-Salvador

Best regards
Andreas

Nicolas Simar wrote:
> I am suggesting to add that point to the next perfsonar meeting.
> The objectives would be to define the problem, its dependencies and
> assess the different solutions.
>
> I would foresee:
> - visualisation tools: AH, ?
> - LS: MG, MS
> - Tools: VV, JB
>
> Cheers,
> Nicolas
>
> Vedrin Jeliazkov wrote:
>> Hi Nicolas, All,
>>
>> Support for perfSONAR service redundancy hasn't been much discussed
>> up to now
>> AFAIK. This might make it rather tricky for quick
>> implementation/deployment.
>>
>> As far as perfsonarUI is concerned, we can imagine the following
>> procedure:
>>
>> 1) LS provides info in some pre-defined and well known way whether a
>> given
>> service has several instances and where they can be reached;
>>
>> 2) perfsonarUI randomly selects one of those instances and sends a
>> query; if
>> the service returns some unexpected error or the query timeouts, then
>> the
>> client asks another randomly chosen service instance; this process
>> continues
>> until either the query is answered or the list of available service
>> instances
>> is exhausted;
>>
>> In fact, this pretty much follows the way how DNS stuff works.
>>
>> Kind regards,
>> Vedrin
>>
>> Nicolas Simar 
>> <>
>>  wrote:
>>
>>
>>> Hi,
>>>
>>> for the deployment of the MDM service on GEANT, the DANTE operation
>>> team mentioned that they would wish to have the services backup-ed
>>> on a second server.
>>>
>>> How can this be done? (a) for the next three months, (b) for the
>>> next release?
>>>
>>> 1) SSH telnet MP - two deployments each contacting the routers. No
>>> issues foreseen.
>>>
>>> 2) RRD MA - two deployments, how do they access the data? The
>>> original DB might be on another server, how do you synchronize
>>> those? Do you foresee another way of doing this?
>>> Obviously if the server where the original data are is down, we
>>> can't do anything except if there are two instance capturing the data.
>>>
>>> 3) L2 status MP - two deployments, each accessing the XML file
>>> stored locally for one server, in another place for the other.
>>> Obviously if the server where the original data are is down, we
>>> can't do anything except if there are two instance capturing the data.
>>>
>>> 4) SQL MA - two deployments. What do you suggest to do with the DB?
>>> Stored where? Any suggestions.
>>>
>>> 5) LS - how two instance of the LS could have the same information?
>>> (can the services register to two LSes at the same time)
>>>
>>> 6) How would the LS advertise the fact that there are two
>>> web-services offering the same information?
>>>
>>> 7) How does the visualisation tools react to have two services
>>> offering the same information? How would they react when one goes down?
>>>
>>> Thanks a lot in advance
>>>
>>> Cheers,
>>
>>
>>
>>
>

-- 
Andreas Hanemann, 

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