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.

3.3 Upgrading the Unbreakable Enterprise Kernel

Oracle Linux 6 Update 8 ships with the latest Unbreakable Enterprise Kernel Release 2 for i386 and Unbreakable Enterprise Kernel Release 4 for x86-64. If you upgrade your system from the installation media, there are five upgrade scenarios:

  • If the UEK R2 or UEK R4 is not currently installed on the system, only the latest Red Hat Compatible Kernel is installed. The UEK R2 or UEK R4 kernel is not installed.

  • If UEK R2 is currently installed on an i386 system, the latest version of the UEK R2 kernel is installed.

  • If UEK R2 is currently installed on an x86-64 system and you upgrade using the Oracle Linux 6 Update 8 installation media for x86-64, which do not contain a UEK R2 repository, the latest version of UEK R2 is not installed.

  • If UEK R3 is currently installed on an x86-64 system and you upgrade using the Oracle Linux 6 Update 8 installation media for x86-64, which do not contain a UEK R3 repository, the latest version of UEK R3 is not installed.

  • If UEK R4 is currently installed on an x86-64 system, the latest version of the UEK R4 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, the latest UEK R3 packages in the ol6_UEKR3_latest repository, and the latest UEK R4 packages in the ol6_UEKR4 repository.

If you want to install the latest UEK R2 kernel on an i386 or x86-64 system, subscribe your system to the ol6_i386_UEK_latest or ol6_x86_64_UEK_latest channel on ULN, or enable the ol6_UEK_latest repository. For example:

# yum-config-manager --enable ol6_UEK_latest

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 enable the ol6_UEKR3_latest repository. For example:

# yum-config-manager --enable ol6_UEKR3_latest

If you want to update an x86-64 system to use the latest UEK R4 kernel, subscribe your system to the ol6_x86_64_UEKR4 channel on ULN, or or enable the ol6_UEKR4 repository. For example:

# yum-config-manager --enable ol6_UEKR4