perfSONAR User Q&A and Other Discussion

["Garnizov, Ivan (RRZE)" <>]

Hello Murilo,

 

Would it be possible for you also to give some more light on the idea of RNP to use the context switching?

IMO the context switching you are trying to configure relies on IP routing inside the network contexts. The question here is, if layer2 measurements would have been sufficient to accomplish the goals of your project. An example of this would be a tool, which would allow you to perform L2 measurements in any L2 segment (virtual interface). The tool does not have limits and support multiple L2 segmentation technologies and it is a matter of a parameter switch to switch the segments.

Here is a link to the tool: https://github.com/jwbensley/Etherate ( there is also EtherateMT )

 

Please note: AFAIK there is still no commitment for this tool to be added to the pS supported tools, but your feedback will be valued.

 

 

Best regards,

Ivan

 

Jubiläumsjahr 2018 - IT in Bewegung

Das RRZE - der IT-Dienstleister der FAU

www.50-jahre.rrze.fau.de

 

From: Murilo Vetter [mailto:]
Sent: Donnerstag, 7. Juni 2018 13:40
To: Mark Feit <>
Cc: Garnizov, Ivan (RRZE) <>; perfsonar-user <>
Subject: Re: [perfsonar-user] Re: Running pscheduler inside a linux namespace

 

Thanks Mark for the clarification.

 

Bests,

--

 

Murilo Vetter
Analista REMEP-FLN/PoP-SC
PoP-SC - Ponto de Presença da RNP em Santa Catarina
REMEP-FLN - Rede Metropolitana de Educação e Pesquisa da Região de Florianópolis
RNP - Rede Nacional de Ensino e Pesquisa
UFSC - Universidade Federal de Santa Catarina
SETIC - Superintendência de Governança Eletrônica e Tecnologia da Informação e Comunicação
Fundações de Apoio FEESC e FEPESE
--/--

www.pop-sc.rnp.br
remep.pop-sc.rnp.br
CHAMADOS:
+55(48)3721-3000
INOC: 11242*100

 

---

De: "Mark Feit" <>
Para: "Murilo Vetter" <>, "Garnizov, Ivan (RRZE)" <>
Cc: "perfsonar-user" <>
Enviadas: Quarta-feira, 6 de junho de 2018 14:07:59
Assunto: Re: [perfsonar-user] Re: Running pscheduler inside a linux namespace

 

Murilo Vetter writes:

 

# pscheduler task --context '{ "schema": 1, "contexts": [ [ { "context": "linuxnns", "data": { "namespace": "ns-ens224" } } ], [ { "context": "linuxnns", "data": { "namespace": "ns-ens256" } } ] ] }' throughput --source 192.168.0.39 --dest 192.168.0.45 --source-node 192.168.0.43 --dest-node 192.168.0.43
Submitting task...
Unable to post task: Error while tasking 192.168.0.43: Unable to post task to 192.168.0.43: ERRO: Task already exists. All participants must be on separate systems.

 

Would it have a way to overcome this error, forcing to do the test? Maybe in a future implementation? Or it is not suppose to?

I tried with 2 different IP on the same host with no namespace configured and it showed the same problem.

 

pScheduler does not allow running of multi-participant tests (throughput and simplestream) where the same server acts as more than one of the participants.  Part of it has to do with the way the API’s resource model is organized and part of it has to do with avoiding running resource-intensive tests on the same server at the same time and getting distorted results.  Any of the single-participant tests (rtt, trace, latency) will work because there’s no second pScheduler involved and they do everything necessary to exercise the namespace changes.  For those, you’d specify a source, a source node and a destination.

 

I do my testing of this on pairs of VMs with a private segment between them.  There’s a utility script in the sources that does the alternate namespace setup and can be customized for your environment:  https://github.com/perfsonar/pscheduler/blob/master/scripts/create-netns

 

--Mark