Testing the UI

From Gridkaschool

Please note

If your reached this point: well done! Before you continue testing the user interface you have to understand a few things.

  • The services (siteBDII, batchsystem and CREAM compute element) you have setup so far are required for a Grid site offering compute resources to remote users.
  • The integration of your recently configured Grid site into the production mode Grid information system is out of scope
  • As consequence (and for other reason also) your Grid site is not part of the Grid that you configured your user interface for. Nevertheless, you can use the user interface to submit a job to your CREAM compute element.

The next steps will guide you through various process you may need to execute on a user interface (e.g. user account creation, deployment of user certificates, information system querying and job submission).

Initial Steps

Initially the user interface does not have any local users. Before you submit a test job, create a local user account

adduser <your_name>
id <your_name>

copy your user certificate to the local users directory.

scp -r <GKS_UI>:~/.globus/ root@<your_UI>:/home/<your_name>/

and set the ownership on the .globus directory on your UI

chown <your_name>: -R .globus/

Test proxy creation

Before users submit jobs to the grid, they have to create a proxy. As member of the dech virtual organization you should test

  • to create proxy using grid-proxy-init
voms-proxy-init --voms dech
Enter GRID pass phrase:
Your identity: /C=DE/O=GermanGrid/OU=TU-Dortmund/CN=Stefan Freitag
Creating temporary proxy ........................................ Done
Contacting  glite-io.scai.fraunhofer.de:15000 [/C=DE/O=GermanGrid/OU=Fraunhofer SCAI/CN=host/glite-io.scai.fraunhofer.de] "dech" Done
Creating proxy ..................... Done
Your proxy is valid until Thu Aug  5 00:57:53 2010

If you experience an error while proxy creation like the following

Contacting  glite-io.scai.fraunhofer.de:15000 [/C=DE/O=GermanGrid/OU=Fraunhofer] "SCAI/CN=host/glite-io.scai.fraunhofer.de" Failed

Error: dech: Unable to satisfy G/SCAI/CN=host/glite-io.scai.fraunhofer.de Request!

None of the contacted servers for SCAI/CN=host/glite-io.scai.fraunhofer.de were capable
of returning a valid AC for the user.

have a look at the file /opt/glite/etc/vomses/dech-glite-io.scai.fraunhofer.de and fix the broken contact string by changing

"/O=GermanGrid/OU=Fraunhofer" "SCAI/CN=host/glite-io.scai.fraunhofer.de"

to

"/O=GermanGrid/OU=Fraunhofer SCAI/CN=host/glite-io.scai.fraunhofer.de"

If the problem still exists you can try also to remove the dech subdirectory from /etc/grid-security/vomsdir/ (which is more a quick hack than a proper solution).

  • to display proxy information using grid-proxy-info -all
glite-voms-proxy-info --all

subject   : /C=DE/O=GermanGrid/OU=TU-Dortmund/CN=Stefan Freitag/CN=proxy
issuer    : /C=DE/O=GermanGrid/OU=TU-Dortmund/CN=Stefan Freitag
identity  : /C=DE/O=GermanGrid/OU=TU-Dortmund/CN=Stefan Freitag
type      : proxy
strength  : 1024 bits
path      : /tmp/x509up_u10022
timeleft  : 11:59:58
=== VO dech extension information ===
VO        : dech
subject   : /C=DE/O=GermanGrid/OU=TU-Dortmund/CN=Stefan Freitag
issuer    : /C=DE/O=GermanGrid/OU=Fraunhofer SCAI/CN=host/glite-io.scai.fraunhofer.de
attribute : /dech/Role=NULL/Capability=NULL
timeleft  : 11:59:57
uri       : glite-io.scai.fraunhofer.de:15000
  • to destroy a proxy using glite-voms-proxy-destroy
glite-voms-proxy-destroy
glite-voms-proxy-info --all

Couldn't find a valid proxy.

Query information providers

The user interface also offers possibilities to access the gLite information system.

  • Get informations about compute elements using lcg-info
lcg-info --list-ce --vo dech --debug
  • Get informations about storage elements using lcg-info
lcg-info --list-se --vo dech --debug
  • Get informations about storage elements using lcg-infosites
lcg-infosites --vo dech se
  • Use ldap to get information from your compute element
ldapsearch -x -H ldap://<FQHN of your compute element>:2170 -b o=grid

Job submission

Before submitting a job to a CREAM compute element you can check if you are allow for job submission. This can be done via the glite-ce-allowed-submission command.

glite-ce-allowed-submission <FQHN of your compute element>:8443

If everything is fine, you should get back

Job Submission to this CREAM CE is enabled

Create a job description

For testing we submit a simple job that idles on the worker node for half a minute and then finished. No input/ output files have to be transferred to/fro the worker node.

[
 Type = "Job";
 JobType = "Normal";
 executable="/bin/sleep";
 arguments="30";
]

Save the above job description in the file sleep.jdl.

Submit a job

To submit the job to your CREAM compute element you can use the command glite-ce-job-submit.

glite-ce-job-submit -a -r <FQHN of your compute element>:8443/cream-pbs-<queue> sleep.jdl

You can also submit the job via the workload management system to your CREAM compute element

glite-wms-job-submit -a --vo dech -r <FQHN of your compute element>:8443/cream-pbs-<queue> sleep.jdl

The status of the job can be checked via glite-ce-job-status.