The Unbreakable Enterprise Kernel (UEK) is a Linux kernel built by Oracle and supported via Oracle Linux support. Oracle Linux and Unbreakable Enterprise Kernel (UEK) Releases. UEK is a Linux kernel that Oracle created to address the needs of customers running demanding software such as Oracle Database on large. Unbreakable Enterprise Kernel (UEK) – based on newer mainline Linux kernel versions, with Oracle's own enhancements for OLTP, InfiniBand, SSD disk access ,. What is the Unbreakable Linux Kernel (UEK)?.