Hi Jianwu,

  The ssh connection is first set up by answering an RSA token password 
followed by a system password.  The RSA token based password changes every few 
seconds.  Since there are many steps (commands) to the remote workflow 
execution we can't have every connection prompt for these dynamic passwords.  
Therefore it must use the preexisting/authenticated connection.  With ssh the 
first connection becomes the master and subsequent ones go straight to the 
prompt.  You can try that yourself.  But with Kepler it would have to either 
establish the master, or use the existing system one.  If it were to use the 
system connection there is no password to provide.  If it were to establish the 
master connection it would have to answer two passwords prompted by different 
screen questions.
  The bottom line is that Kepler does not seem to share in the externally 
established SSH connection.  I will have to research the JSCH library for more 
information on this mode of operation as well.

Thanks,
Eduardo

From: Jianwu Wang <[email protected]<mailto:[email protected]>>
Date: Thursday, November 1, 2012 8:12 PM
To: "Valente, Eduardo G. (GSFC-610.3)[GLOBAL SCIENCE & TECHNOLOGY INC]" 
<[email protected]<mailto:[email protected]>>
Cc: Norbert Podhorszki <[email protected]<mailto:[email protected]>>, 
"[email protected]<mailto:[email protected]>" 
<[email protected]<mailto:[email protected]>>
Subject: Re: [kepler-users] Sample workflow using JobSubmission/JobManager

Hi Eduardo,

    If you start kepler from kepler.sh/kepler.bat, not double-clicking kepler 
icon, a console will show up and it normally has more information on errors.

    I checked the '-M' option of ssh and the implementation of ssh related code 
in Kepler. I don't think Kepler supports control master. I also don't see the 
Jsch library we used for ssh actors support it. So it's hard for us to update 
our code to do it.

    But I think there is still one way workaround. How do you set up the ssh 
connection at the first place? Type your two passwords in command line? Does it 
work if you try it in Kepler using 'SSH Session' actor? The same ssh session 
actor generated by the 'SSH Session' actor can be postponed and shared by other 
workflow executions within the same JVM. To do it, the parameter 'postpone' of 
the actor has to be selected (true) and the 'closeAtEnd' has to be false. So if 
you split the workflow into two workflows. The first workflow only has 'Host' 
and 'SSH Session'. The second one has other parts. If you can generate correct 
ssh session using the first workflow. You can run the second workflow many 
times without creating new ssh sessions. My tests work here.

    I'm ccing the email to Norbert. He is the original developer of the actors 
and workflows. He might have better solutions for you.

Best wishes

Sincerely yours

Jianwu Wang, Ph.D.
[email protected]<mailto:[email protected]>http://users.sdsc.edu/~jianwu/

Assistant Project Scientist
Scientific Workflow Automation Technologies (SWAT) Laboratory
San Diego Supercomputer Center
University of California, San Diego
San Diego, CA, U.S.A.

On 11/1/12 2:08 PM, Valente, Eduardo G. (GSFC-610.3)[GLOBAL SCIENCE & 
TECHNOLOGY INC] wrote:
The failure is graceful in that the session return true for the failed port.  
If there is a way to view logs for that actor please let me know.

Two factor authentication is the use of two passwords in the admission process 
one of which utilizes an RSA token (changes every 30 seconds or so).

This means that it becomes impractical to automate processes if every time we 
ssh the password is different.  And this two factor authentication cannot be 
bypassed with public keys (otherwise known as passwordless ssh).  The only 
option left is to use an existing ssh connection enabled as the control master. 
Generally the –M switch of ssh clients.  But it would appear the java ssh 
client and the system ssh client do not "see" each other.  If that is the case 
than the java version would need such a mode as well.  Currently I see two 
modes: interactive with password request and passwordless with identity file.

I cannot otherwise provide you a means to recreate the environment we have.  
But look into the concept of control master and you will be able to investigate 
this possibility with the ssh session actor.

Thanks,
Eduardo

From: Jianwu Wang <[email protected]<mailto:[email protected]>>
Date: Thursday, November 1, 2012 4:52 PM
To: "Valente, Eduardo G. (GSFC-610.3)[GLOBAL SCIENCE & TECHNOLOGY INC]" 
<[email protected]<mailto:[email protected]>>
Cc: "[email protected]<mailto:[email protected]>" 
<[email protected]<mailto:[email protected]>>
Subject: Re: [kepler-users] Sample workflow using JobSubmission/JobManager

Hi Eduardo,

    So you failed even just using 'SSH Session' actor? Did you get any error or 
exception message? It's new to me for the two-factor authentication. If you 
tell me how to reproduce it, I can dig into it and check what went wrong.

Best wishes

Sincerely yours

Jianwu Wang, Ph.D.
[email protected]<mailto:[email protected]>http://users.sdsc.edu/~jianwu/<http://users.sdsc.edu/%7Ejianwu/>

Assistant Project Scientist
Scientific Workflow Automation Technologies (SWAT) Laboratory
San Diego Supercomputer Center
University of California, San Diego
San Diego, CA, U.S.A.

On 11/1/12 1:45 PM, Valente, Eduardo G. (GSFC-610.3)[GLOBAL SCIENCE & 
TECHNOLOGY INC] wrote:
Thanks.  The workflow crashes kepler at a "type detection" step.  So I am 
trying just the SSH session step for starters.  I am running in an environment 
with two-factor authentication.  So I authenticate ssh with control master 
enabled hoping that subsequent ssh attempts by kepler use the existing open 
connection.   At the kepler workflow I set up the ssh session with an identity 
file hoping it would use the control master session, but it is failing to do 
so.  Any thoughts on this mode of operation?
Eduardo

From: Jianwu Wang <[email protected]<mailto:[email protected]>>
Date: Wednesday, October 31, 2012 5:50 PM
To: "Valente, Eduardo G. (GSFC-610.3)[GLOBAL SCIENCE & TECHNOLOGY INC]" 
<[email protected]<mailto:[email protected]>>
Cc: "[email protected]<mailto:[email protected]>" 
<[email protected]<mailto:[email protected]>>
Subject: Re: [kepler-users] Sample workflow using JobSubmission/JobManager

Hi Eduardo,

    A sample workflow using JobSubmission/JobManager can be found at 
https://code.kepler-project.org/code/kepler/trunk/workflows/SC06-Tutorial/JobSubmission.xml.
 To use it in PBS environment,  you just need to edit the 'JobManager' 
parameter to be 'PBS'. Other parameters such as 'SimTarget' and 'JobScript' 
also need to be configured to fit your information.

Best wishes

Sincerely yours

Jianwu Wang, Ph.D.
[email protected]<mailto:[email protected]>http://users.sdsc.edu/~jianwu/<http://users.sdsc.edu/%7Ejianwu/>

Assistant Project Scientist
Scientific Workflow Automation Technologies (SWAT) Laboratory
San Diego Supercomputer Center
University of California, San Diego
San Diego, CA, U.S.A.

On 10/31/12 2:22 PM, Valente, Eduardo G. (GSFC-610.3)[GLOBAL SCIENCE & 
TECHNOLOGY INC] wrote:
Does anyone have a sample workflow that exercises a PBS based HPC environment 
that they would like to share?
Thanks.




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  • [kep... Valente, Eduardo G. (GSFC-610.3)[GLOBAL SCIENCE & TECHNOLOGY INC]
    • ... Jianwu Wang
      • ... Valente, Eduardo G. (GSFC-610.3)[GLOBAL SCIENCE & TECHNOLOGY INC]
        • ... Jianwu Wang
    • ... Jianwu Wang
      • ... Valente, Eduardo G. (GSFC-610.3)[GLOBAL SCIENCE & TECHNOLOGY INC]
        • ... Jianwu Wang
    • ... Valente, Eduardo G. (GSFC-610.3)[GLOBAL SCIENCE & TECHNOLOGY INC]

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