Installation of a CREAM CE

The CREAM CE can be installed via yum. All glite yum repositories are available at http://grid-deployment.web.cern.ch/grid-deployment/glite/repos/. For the CREAM CE select release 3.2.

The required repositories are:

 dag.repo
 glite-TORQUE_utils.repo
 glite-CREAM.repo
 lcg-CA.repo

The repository files have to be stored in directory /etc/yum.repos.d/. The DAG repository has to be replaced:

cd /etc/yum.repos.d
rm -f dag.repo
wget -P /etc/yum.repos.d/ http://grid-deployment.web.cern.ch/grid-deployment/glite/repos/3.2/dag.repo
wget -P /etc/yum.repos.d/ http://grid-deployment.web.cern.ch/grid-deployment/glite/repos/3.2/glite-CREAM.repo
wget -P /etc/yum.repos.d/ http://grid-deployment.web.cern.ch/grid-deployment/glite/repos/3.2/glite-TORQUE_utils.repo
wget -P /etc/yum.repos.d/ http://grid-deployment.web.cern.ch/grid-deployment/glite/repos/3.2/lcg-CA.repo

Installing the packages

Now the software has to be installed. Aside from the CREAM Compute Element packages you need also to install the Torque client software.

yum install glite-CREAM glite-TORQUE_utils
yum install lcg-CA

If asked to accept importing the gpg keys of the repository answer with "y":

Importing GPG key 0x836AAC2B "Gd Integration <gd-release-team@cern.ch>" from http://glite.web.cern.ch/glite/glite_key_gd.asc
Is this ok [y/N]: y

Additionally the certificates of all VOMS server for VOs supported by your site have to be stored in the directory /etc/grid-security/vomsdir. In our case this is glite-io.scai.fraunhofer.de.pem for dech VO.

Exercise:
Download the dech VOMS certifiacte from the CIC portal (http://cic.gridops.org/index.php?section=home) and save it under /etc/grid-security/vomsdir/glite-io.scai.fraunhofer.de.pem. Alternatively you can get the certificate from http://gkswiki.fzk.de/images/4/4a/Dech_certificate.pem.

mkdir -p /etc/grid-security/vomsdir
wget http://gkswiki.fzk.de/images/4/4a/Dech_certificate.pem -O /etc/grid-security/vomsdir/glite-io.scai.fraunhofer.de.pem

Check the contents (validity, issuer, ...) of the downloaded certificate by

cd /etc/grid-security/vomsdir/
openssl x509 -in glite-io.scai.fraunhofer.de.pem -text -noout

The output of this command is given below

Certificate:
   Data:
       Version: 3 (0x2)
       Serial Number: 10039 (0x2737)
       Signature Algorithm: sha1WithRSAEncryption
       Issuer: C=DE, O=GermanGrid, CN=GridKa-CA
       Validity
           Not Before: Nov 13 15:37:26 2009 GMT
           Not After : Dec 13 15:37:26 2010 GMT
       Subject: C=DE, O=GermanGrid, OU=Fraunhofer SCAI, CN=host/glite-io.scai.fraunhofer.de
       ...

A basic validity check for the certificate can be performed with

openssl verify -CApath /etc/grid-security/certificates/ /etc/grid-security/vomsdir/glite-io.scai.fraunhofer.de.pem

The output should be

/etc/grid-security/vomsdir/glite-io.scai.fraunhofer.de.pem: OK

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Proceed to the CREAM CE Configuration

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Go back to CREAM CE, gLite Administration Course