Re: [Condor-users] User impersonation

[Ralf Reinhardt <ralf.reinhardt@xxxxxxxxxxx>]

Mark Silberstein wrote:
> I'm not sure I understood what exactly you want to achieve. Say, you
> have a web portal. Your users invoke an application via this portal and
> are not aware of Condor behind the curtain. Each invocation results in
> multiple jobs submission to Condor. All jobs are submitted under the
> same user ( right? ), and are run one after another. However you want to
> have interleaving, i.e., if we mark all jobs of user1 as 1, user2 as 2
> and etc, than the submission:
> 11112222 should run as 121212? Is it correct? 
Exactly!
> If yes, I think there are several solutions. 
> 1) You have this "runas" command, which allows you to run things under
> another user ID. so if you submit with this "runas" it should work the
> way you want. The only problem is that you have to have all the users on
> the submission machine and they should pass their password as a
> parameter to runas.
runas itself is not a feasible solution because it needs an interactive 
input of username and password. There are other implementations that 
allow you to send the password as an argument but the output is not 
redirected to stdout, which means that i cannot read the 
clusternumber... Windows pipes have a simple Unix like interface which 
does not work in complex situations and a very complicated native 
interface that is somehow beyond my comprehension :-(
For the moment I use CreateProcessAsUser and redirect the ouput to a 
file which gets read afterwards. Really wierd, especially because I have 
to create the users using the Windows ADSI interface under C++ (just 
painful).
> 2) Another way ( not sure if it works though) is to run multiple schedds
> every time new user submits new jobs - one schedd per virtual user. If
> it works, the only thing you need is a script to kill schedd after it
> finishes all the jobs. If it works, it seems to be the easiest thing to
> do.
That sounds interesting, though I'm not sure if the system behaves 
better if I add 20-30 schedd instances (see my post about extremly small 
jobs..)
> 3) And finally, you can play with job priority in the queue, 
> periodically updating the queue according to the number of users  you
> have.
Before I intervene into the scheduling of condor, I restart my project 
using SGE or Maui. Intelligent scheduling is the task of Condor, not mine.


Cheers   Ralf