{prereqat least 20 GB and recommend 80GB hard drive spaceoracle javainstall oracle java with following stepsalternatives --install /usr/bin/java java /usr/java/jdk1.7.0_51/bin/java 2[root@spacewalk ~]# alternatives --config javaThere are 2 programs which provide 'java'. Selection Command-----------------------------------------------*+ 1 /usr/lib/jvm/jre-1.4.2-gcj/bin/java 2 /usr/java/jdk1.7.0_51/bin/javaEnter to keep the current selection[+], or type selection number: 2for referencehttp://wiki.comdivision.com/display/cdconstech/Switch+Java+on+CentOS}wget http://yum.spacewalkproject.org/2.0/RHEL/5/i386/spacewalk-repo-2.0-3.el5.noarch.rpmrpm -Uvh spacewalk-repo-2.0-3.el5.noarch.rpmvi /etc/yum.repos.d/jpackage-generic.repo{add following[jpackage-generic]name=JPackage generic#baseurl=http://mirrors.dotsrc.org/pub/jpackage/5.0/generic/free/mirrorlist=http://www.jpackage.org/mirrorlist.php?dist=generic&type=free&release=5.0enabled=1gpgcheck=1gpgkey=http://www.jpackage.org/jpackage.asc}wget http://dl.fedoraproject.org/pub/epel/5/i386/epel-release-5-4.noarch.rpmrpm -Uvh epel-release-5-4.noarch.rpmyum install postgresql-server spacewalk-postgresqlyum install -y 'postgresql-server > 8.4'chkconfig postgresql onservice postgresql initdbservice postgresql start{configure postgresqlsu - postgres -c 'PGPASSWORD=nokia420; createdb spaceschema ; createlang plpgsql spaceschema ; yes $PGPASSWORD | createuser -P -sDR admin'edit the file /var/lib/pgsql/data/pg_hba.confadd following lineslocal spaceschema admin md5host spaceschema admin 127.0.0.1/8 md5host spaceschema admin ::1/128 md5local spaceschema postgres ident}service postgresql reload/restart{test the connection.PGPASSWORD=nokia420 psql -a -U admin spaceschemaPGPASSWORD=nokia420 psql -h localhost -a -U admin spaceschema}{tune databaseyum install pgtunepgtune --type=web -c 600 -i /var/lib/pgsql/data/postgresql.conf >/tmp/pgtune.confdiff -u /var/lib/pgsql/data/postgresql.conf /tmp/pgtune.confcp /var/lib/pgsql/data/postgresql.conf /var/lib/pgsql/data/postgresql.conf.bakcp /tmp/pgtune.conf /var/lib/pgsql/data/postgresql.confservice postgresql restart}{yum install spacewalk-postgresql xml-commons-apis}{spacewalk-setup --disconnected --external** Database: Setting up database connection for PostgreSQL backend.Hostname (leave empty for local)?Database? spaceschemaUsername? adminPassword?** Database: Populating database.*** Progress: ######Note: just if this process gets exist with this error (Could not populate database.)then check the logs in /var/log/rhn/populate_db.log.*if the errors says psql:/etc/sysconfig/rhn/postgres/deploy.sql:14681: ERROR: language "" does not existHINT: Use CREATE LANGUAGE to load the language into the database.then execute following command and rerun spacewalk-setup again su - postgres -c 'createlang pltclu spaceschema ;'spacewalk-setup --disconnected --external}