[[PageOutline]] 
= Introduction =
The QCG-!SimpleClient is a basic client utility used to submit jobs to the QCG-Broker service (a [http://www.qoscosgrid.org QosCosGrid] meta-scheduler). Its job description format (QCG-Script) and command tools syntax were intentionally modelled after local batch systems "look && feel". Thus, the learning effort needed for a new users (that have some experience with local cluster systems) was very limited. The QCG-!SimpleClient allow you to submit MUSCLE job in the coherent way to any single PL-Grid site. Unfortunately current version of QCG-Script do not support description of more advance experiments like co-allocated (cross-cluster) simulations, workflows or parameter sweep. You need to use [[QCG-AdvancedClient]] instead.

= User Interface Machine =
Every cluster in PL-Grid can be accessed from the QCG UI machine: qcg.man.poznan.pl. You can log in there using your PL-Grid account:
{{{
ssh plg[your-id]@qcg.man.poznan.pl
}}}
= Preparing credentials =
1. Copy your credentials (PKCS12 keystore) to the qcg machine:
{{{
scp plg[your-id].p12 plg[your-id]@qcg.man.poznan.pl:~/
}}}
2. Create `~/.globus` directory
{{{
mkdir ~/.globus
}}}
3. Convert your credentials to the `.pem` format
{{{

$ openssl pkcs12 -nocerts -in usercred.p12 -out ~/.globus/userkey.pem
$ openssl pkcs12 -clcerts -nokeys -in usercred.p12 -out ~/.globus/usercert.pem
$ chmod 644 ~/.globus/usercert.pem
$ chmod 400 ~/.globus/userkey.pem
}}}

= Submitting Simple Bash job =
* Example job script:
{{{
$cat hostname.qcg 
#cluster where to run a job
#QCG host=zeus.cyfronet.pl
#QCG output=output.txt
#QCG error=error.txt

/bin/hostname
date
sleep 30
date
sleep 30
date

}}}
* job submission:
{{{
$qcg-sub hostname.qcg 
https://elder6.man.poznan.pl:8443/qcg/services/
/C=PL/O=GRID/O=PSNC/CN=qcg-broker/qcg-broker.man.poznan.pl
UserDN = /C=PL/O=GRID/O=PSNC/CN=Mariusz Mamonski
ProxyLifetime = 23 Days 11 Hours 54 Minutes 8 Seconds

jobId = J1349800941529__3789
}}}
* list all your jobs:
{{{
$qcg-list 
https://elder6.man.poznan.pl:8443/qcg/services/
/C=PL/O=GRID/O=PSNC/CN=qcg-broker/qcg-broker.man.poznan.pl
UserDN = /C=PL/O=GRID/O=PSNC/CN=Mariusz Mamonski
ProxyLifetime = 23 Days 11 Hours 53 Minutes 52 Seconds

JOB IDENTIFIER                  TASK      NOTE                  SUBMISSION TIME  START TIME       FINISH TIME      STATUS            HOSTNAME  

J1349800941529__3789            task                            09.10.12 18:42                                     PENDING           zeus      

Number of tasks:
PENDING : 1
TOTAL: 1
}}}

* get detailed job info:
{{{
> qcg-info J1349800941529__3789
https://elder6.man.poznan.pl:8443/qcg/services/
/C=PL/O=GRID/O=PSNC/CN=qcg-broker/qcg-broker.man.poznan.pl
UserDN = /C=PL/O=GRID/O=PSNC/CN=Mariusz Mamonski
ProxyLifetime = 23 Days 11 Hours 52 Minutes 53 Seconds

Note: 
TaskType: SINGLE
SubmissionTime: Tue Oct 09 18:42:21 CEST 2012
FinishTime: 
ProxyLifetime: P23DT11H52M51S
Status: RUNNING
StatusDesc: 
StartTime: Tue Oct 09 18:42:21 CEST 2012

Allocation: 
HostName: zeus.cyfronet.pl
ProcessesCount: 1
ProcessesGroupId: 
Status: RUNNING
StatusDescription: 
SubmissionTime: Tue Oct 09 18:42:21 CEST 2012
FinishTime: 
LocalSubmissionTime: Tue Oct 09 18:42:24 CEST 2012
LocalStartTime: Tue Oct 09 18:42:54 CEST 2012
LocalFinishTime: 

}}}
* peek job output when its running:
{{{
$  qcg-peek J1349800941529__3789
https://elder6.man.poznan.pl:8443/qcg/services/
/C=PL/O=GRID/O=PSNC/CN=qcg-broker/qcg-broker.man.poznan.pl
UserDN = /C=PL/O=GRID/O=PSNC/CN=Mariusz Mamonski
ProxyLifetime = 23 Days 11 Hours 53 Minutes 14 Seconds

n1-3-12.local
Tue Oct  9 18:42:54 CEST 2012

}}}
* when jobs is finished the outputs should be in the directory from where you submitted your job:
{{{
$ cat output.txt 
n1-3-12.local
Tue Oct  9 18:42:54 CEST 2012
Tue Oct  9 18:43:24 CEST 2012
Tue Oct  9 18:43:54 CEST 2012

}}}
= MUSCLE job example =
{{{
#QCG name=SimpleExamples
#QCG host=zeus.cyfronet.pl
#QCG walltime=PT14H

#QCG stage-in-file=SimpleExample.cxa.rb

#QCG application=muscle2
#QCG argument=SimpleExample.cxa.rb

#QCG stage-out-dir=. -> results-${JOB_ID}
#QCG output=output-${JOB_ID}.txt
#QCG error=output-${JOB_ID}.txt
}}}

= Interactive jobs =
With QCG it is possible to start an interactive session with any of the PL-Grid clusters. You can use it to compile your application  or to perform some debug runs. Example script:
{{{
#QCG host=inula.man.poznan.pl
#QCG walltime=PT3H

/bin/bash
}}}
Example interactive session:
{{{
$ qcg-interactive interactive-reef.qcg 
https://qcg-broker.man.poznan.pl:8443/qcg/services/
/C=PL/O=GRID/O=PSNC/CN=qcg-broker/qcg-broker.man.poznan.pl
UserDN = /C=PL/O=GRID/O=PSNC/CN=Mariusz Mamonski
ProxyLifetime = 20 Days 2 Hours 28 Minutes 44 Seconds

jobId = J1350912281097__5242
Press Ctrl-C to cancel the task
Interactive session started. Use the 'exit' command to quit.
[r473] /home/plgrid/plgmamonski/reef/J1350912281097__5242_task_1350912283206_133 > module load muscle2
 plgrid/tools/java/jdk1.6.0_23 load complete.
 intel/10.1 load complete.
 'plgrid/tools/openmpi/current' load complete.
[r473] /home/plgrid/plgmamonski/reef/J1350912281097__5242_task_1350912283206_133 > muscle2  --cxa /home/plgrid-groups/plggmuscle/2.0/devel-debug/share/muscle/examples/cxa/SimpleExample.cxa.rb --main r w 
Running both MUSCLE2 Simulation Manager and the Simulation
=== Running MUSCLE2 Simulation Manager ===
...
}}}
Other valid `#host` values:
 * zeus.cyfronet.pl (Cyfronet),
 * galera.task.gda.pl (TASK),
 * hydra.icm.edu.pl (ICM),
 * reef.man.poznan.pl (PSNC),
 * inula.man.poznan.pl (PSNC).
= Further reading =
 * [http://apps.man.poznan.pl/trac/muscle/raw-attachment/wiki/QCG-SimpleClient/QCG-SimpleClient-CheatSheet.pdf QCG-SimpleClient Cheet Sheet Card]