[Bigjob-users] Problems with BigJob example

[Ole Weidner]

Hi Andre,

so BigJob uses SAGA to launch the agents (e.g., via Globus) but the agents (called sub-jobs?) internally always use (password-less) SSH to launch the 'work units' they pull? 

If that's the case, was that a design decision based on a typical HPC cluster setup (with password-less ssh enabled for MPI)? Is this method sufficient for non-HPC grids, like, e.g., OSG (glidein-wms) as well? Naively, I would assume 'yes', since in an OSG-type of environment, the agent will eventually end-up on an HPC-cluster as well.

Thanks,
Ole

On Jan 3, 2012, at 8:11 AM, Andre Luckow wrote:

> Hi Ole,
> BigJob doesn't use SAGA for launching jobs - the default job adaptor
> has severe limitations, e.g. it cannot launch MPI jobs or jobs on
> remote machines. The primary use case of BJ is the management of
> multiple nodes. For this purpose, BJ relies on SSH. Since the local
> version is just used for development purposes the same mechanisms are
> applied here.
> 
> Best,
> Andre
> 
> On Tue, Jan 3, 2012 at 2:23 PM, Ole Weidner <oweidner at cct.lsu.edu> wrote:
>> Hi Andre,
>> 
>> I'm a little confused: I thought big-job uses SAGA (and in the case of my example fork://) to launch the sub-jobs? I'm running the example on my local machine were I would like to avoid any type of password-less ssh logins!
>> 
>> Why is ssh required in the fork:// case?
>> 
>> Thanks,
>> Ole
>> 
>> On Jan 3, 2012, at 4:48 AM, Andre Luckow wrote:
>> 
>>> Hi Ole
>>> 
>>>> However, stdout.txt doesn't contain the output of /bin/date but "ssh: connect to host localhost port 22: Connection refused". I have no idea where this comes from.
>>> 
>>> BigJob utilizes SSH for the execution of sub-jobs. Please ensure that
>>> your local SSH daemon is up and running and that you can login without
>>> password.
>>> 
>>> Best,
>>> Andre
>> 
>> _______________________________________________
>> Bigjob-users mailing list
>> Bigjob-users at mail.cct.lsu.edu
>> https://mail.cct.lsu.edu/mailman/listinfo/bigjob-users