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.

4.6 Upgrading the Unbreakable Enterprise Kernel

Oracle Linux 6 Update 5 and later updates ship with the latest Unbreakable Enterprise Kernel Release 2 (UEK R2) for x86 and Unbreakable Enterprise Kernel Release 3 (UEK R3) for x86_64. If you upgrade your system from the installation media, there are four upgrade scenarios:

  • If the UEK Release 2 or Release 3 is not currently installed on the system, only the latest Red Hat Compatible Kernel is installed. The UEK R2 or UEK R3 kernel is not installed.

  • If UEK R2 is currently installed on an x86 system, the latest version of the UEK R2 kernel is installed.

  • If UEK R2 is currently installed on an x86_64 system, the latest version of the UEK R2 kernel is installed unless you enable the UEK R3 repository.

  • If UEK R3 is currently installed on an x86_64 system, the latest version of the UEK R3 kernel is installed.

yum uses whatever repositories you have configured on your system to upgrade it. You can find the latest UEK R2 packages in the ol6_i386_UEK_latest and ol6_x86_64_UEK_latest repositories and the latest UEK R3 packages in the ol6_UEKR3_latest repository.

If you want to install the latest UEK R2 kernel on an x86 or x86_64 system, subscribe your system to the ol6_i386_UEK_latest or ol6_x86_64_UEK_latest channel on ULN, or configure the repository in the appropriate /etc/yum.repos.d/ file as shown here:

[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=https://yum.oracle.com/RPM-GPG-KEY-oracle-ol6
gpgcheck=1
enabled=1

If you want to update an x86_64 system to use the latest UEK R3 kernel, subscribe your system to the ol6_x86_64_UEKR3_latest channel on ULN, or configure the repositories in the appropriate /etc/yum.repos.d/ file as shown here:

[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