Hi Maarten,
On Thu, 2005-06-16 at 01:21 +0200, Maarten Litmaath, CERN wrote:
> On Wed, 15 Jun 2005, Marco La Rosa wrote:
>
> > Hi all,
> >
> > Is there any way to submit a job to a pbs cluster which DOES NOT have
> > globus/LCG installed on any of the compute nodes?
>
> Hi Marco,
> what would be the point of it? A grid job should be able to use grid
> functionality on the WNs, I would say...
>
I agree. The problem is that the computing centres we work with still
think in terms of traditional supercomputing/HPC. I was hoping to try to
"show them the way" by taking small steps ie job submission to PBS from
the CE without globus on the cluster. I am aware that this is a very
'disabled' form of grid (if it can still be called that!) but it is a
start.
> > I know that globus-job-* with the pbs jobmanager works.
> >
> > However, it seems that the edg-job-* tools result in the creation of a
> > wrapper script that uses globus-url-copy (this is in addition to the
> > lcgpbs jobmanager which also uses it) . This script seems to be embedded
> > in the job adaptor (i think) !?!
>
> Indeed: the RB creates the job wrapper script that actually is submitted
> to the CE, where the batch system adapter perl script then embeds it in
> a wrapper that actually gets submitted to the batch system. The RB script
> uses globus-url-copy to transfer the input/output sandbox directly from/to
> the RB. The "lcg" job managers use globus-url-copy to sync the job area
> on the WN with the corresponding area on the CE, in particular to copy a
> renewed proxy from the CE to the WN. (In principle "scp" can be used
> instead, but we would rather not depend on that, because we should move
> toward making it impossible for a job on a WN to access the CE via ssh.)
> The "lcg" job managers are really needed only when the CE and the WNs do
> not share home directories. Any site can cook up their own job manager,
> e.g. to interface to a batch system not directly supported by LCG.
thanx for the info!
>
> > Is there a way to bypass this?
>
> If your job does not have an input/output sandbox and does not use any
> grid functionality, I think the WN does not need Globus/LCG. A typical
> job submitted via an RB will at least have an input sandbox, though,
> viz. to transfer the user's job script...
No point having a resource broker if it's not going to be used : )
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