Oracle Linux 7 with the Unbreakable Enterprise Kernel Release 5 is installed as the default OS. Unbreakable Enterprise Kernel Release 5 contains improvements and new features that have been incorporated into mainline Linux since the previous release of the Unbreakable Enterprise Kernel.
The minimum requirement is the Unbreakable Enterprise Kernel Release 5 Update 1, kernel 4.14.35-1844.2.5. Because Oracle Linux 7 Update 6 default installation is the Unbreakable Enterprise Kernel Release 5 Update 1, kernel 4.14.35-1818.3.3. Update to Unbreakable Enterprise Kernel Release 5 Update 1, kernel 4.14.35-1844.2.5 or later after the Oracle Linux 7 Update 6 installation.
For the latest information about operating system compatibility and pointers to installation information, refer to Oracle Unbreakable Enterprise Kernel Release 5 Release Notes at https://docs.oracle.com/cd/E93554_01/E95779/html/index.html.