perfSONAR User Q&A and Other Discussion

[Jason Zurawski <>]

Hi Craig/All;

Lets see if we can clear up some of what you are asking:

>> 1. I had to add the host IP address to the file 
>> /opt/perfsonar_ps/toolkit/etc/external_addresses in order to establish 
>> communication between the two perfSONAR nodes.  

To answer this, we need to clarify this first:

>> They have valid Internet IP addresses

Do you mean they had an RFC1918 local address, or they had actual public 
addresses and were just cut off from reaching the public internet?  In the 
case of the former, this is well documented on the FAQ:

http://psps.perfsonar.net/toolkit/FAQs.html#Q44

If the later is the case, we may need some more information and log files to 
determine if this a bug.  

>> 2. I was able to schedule a ping test between the nodes, but I am unable 
>> to plot the data.  I go to "Ping Latency" under "Service Graphs" to access 
>> the "PingER Tests" page.  This page shows an active data set.  When I try 
>> to graph the data, a new window opens up, but it doesn't contain a plot.  
>> It appears that the server is trying to access a web application from 
>> google.com in order create the graph.  Is that what's happening? Is there 
>> a way to see the data without Google?  I think the one-way latency and 
>> bandwidth measurements have the same problem.


Lets back up a step or two and explain how the graphs work before we start a 
privacy and data flame war:

1) The graphs are built using the Google Visualization API 
(https://developers.google.com/chart/), and like other javascript 
visualization APIs the source lives in a central location that someone else 
maintains (e.g. Google).  When your client accesses one of the CGI scripts 
the libraries need to be downloaded (e.g. why things didn't work in your 
case). 

2) Rendering of the graph data is done on the client side - e.g. data is not 
sent off to google, although I am sure your client accessing the libraries is 
logged in some mysterious data center in Mountain View CA, and then again in 
Columbia MD.  This is spelled out in one of the development documents:

https://google-developers.appspot.com/chart/interactive/docs/gallery/linechart#Data_Policy

Hope this helps.  

Thanks;

-jason

On Dec 20, 2013, at 12:05 PM, Craig Finch 
<>
 wrote:

> I'm experimenting with a pair of perfSONAR nodes on an isolated network.  
> They have valid Internet IP addresses, but they don't have any access to 
> the outside world.  I have noticed a couple of issues while testing the 
> nodes under this configuration, and I suspect that others will try a 
> similar experiment and run into the same issues.  
> 
> 1. I had to add the host IP address to the file 
> /opt/perfsonar_ps/toolkit/etc/external_addresses in order to establish 
> communication between the two perfSONAR nodes.  
> 
> 2. I was able to schedule a ping test between the nodes, but I am unable to 
> plot the data.  I go to "Ping Latency" under "Service Graphs" to access the 
> "PingER Tests" page.  This page shows an active data set.  When I try to 
> graph the data, a new window opens up, but it doesn't contain a plot.  It 
> appears that the server is trying to access a web application from 
> google.com in order create the graph.  Is that what's happening? Is there a 
> way to see the data without Google?  I think the one-way latency and 
> bandwidth measurements have the same problem.
> 
> Craig Finch
> Postdoctoral Research Associate, STOKES Advanced Research Computing Center
> Institute for Simulation & Training
> University of Central Florida
> 3100 Technology Pkwy., Orlando, FL 32826-0544
> 407-823-0711
>