The software described in this documentation is either in Extended Support or Sustaining Support. See https://www.oracle.com/us/support/library/enterprise-linux-support-policies-069172.pdf for more information.
Oracle recommends that you upgrade the software described by this documentation as soon as possible.

3.2.2 About Oracle Yum Server

Oracle also provides all errata and updates for Oracle Linux via the Oracle Yum Server service, which includes updates to the base distribution, but does not include Oracle-specific software. You do not require an Oracle Linux support subscription to use this service. For more information on how to obtain updates from Oracle Yum Server, see https://yum.oracle.com.

By default, all new installations of Oracle Linux 6 Update 5 are automatically configured to use the Oracle Yum Server update service. If you subsequently register the system with ULN, the Oracle Yum Server service is automatically disabled.

The following entries in the /etc/yum.repos.d/public-yum-ol6.repo file enable you to download the latest available packages for Oracle Linux 6 and the Unbreakable Enterprise Kernel Release 2:

[ol6_latest]
name=Oracle Linux $releasever Latest ($basearch)
baseurl=https://yum.oracle.com/repo/OracleLinux/OL6/latest/$basearch/
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-oracle
gpgcheck=1
enabled=1

[ol6_UEK_latest]
name=Latest Unbreakable Enterprise Kernel for Oracle Linux $releasever ($basearch)
baseurl=https://yum.oracle.com/repo/OracleLinux/OL6/UEK/latest/$basearch/
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-oracle
gpgcheck=1
enabled=1

The following entries in the /etc/yum.repos.d/public-yum-ol6.repo file enable you to download the latest available packages for Oracle Linux 6 and the Unbreakable Enterprise Kernel Release 3:

[ol6_latest]
name=Oracle Linux $releasever Latest ($basearch)
baseurl=https://yum.oracle.com/repo/OracleLinux/OL6/latest/$basearch/
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-oracle
gpgcheck=1
enabled=1

[ol6_UEKR3_latest]
name=Latest Unbreakable Enterprise Kernel Release 3 for Oracle Linux $releasever ($basearch)
baseurl=https://yum.oracle.com/repo/OracleLinux/OL6/UEKR3/latest/$basearch/
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-oracle
gpgcheck=1
enabled=1
Note

The ol6_UEKR3_latest repository is not available for i386 systems.

If you want to install packages from the playground or OFED repositories, add the following entries and enable them by setting the value of enabled to 1:

[ol6_playground_latest]
name=Latest mainline stable kernel for Oracle Linux 6 ($basearch) - Unsupported 
baseurl=https://yum.oracle.com/repo/OracleLinux/OL6/playground/latest/$basearch/
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-oracle
gpgcheck=1
enabled=0

[ol6_ofed_UEK]
name=OFED supporting tool packages for Unbreakable Enterprise Kernel on Oracle Linux 6 ($basearch)
baseurl=https://yum.oracle.com/repo/OracleLinux/OL6/ofed_UEK/$basearch/
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-oracle
gpgcheck=1
enabled=0
Note

On a freshly installed Oracle Linux 6 Update 5 system, the public-yum-ol6.repo file uses the variables uek and uekr3 to enable or disable ol6_UEK_latest and ol6_UEKR3_latest. For an i386 system, the value of uek is set to 1 in /etc/yum/vars/uek to enable ol6_UEK_latest and the value of uekr3 is set to 0 in /etc/yum/vars/uekr3 to disable ol6_UEKR3_latest. For an x86-64 system, the value of uekr3 is set to 1 in /etc/yum/vars/uekr3 to enable ol6_UEKR3_latest and the value of uek is set to 0 in /etc/yum/vars/uek to disable ol6_UEK_latest.

If you subsequently register the system with ULN, the repository entries in public-yum-ol6.repo are disabled and the values of both uek and uekr3 are set to 0.