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Unintended default boot kernel changed from RHCK to UEK (Doc ID 2666883.1)

Last updated on JUNE 03, 2022

Applies to:

Oracle Cloud Infrastructure - Version N/A to N/A [Release 1.0]
Linux x86-64


In an Oracle Linux 7 system, default kernel was changed from Oracle's Unbreakable Enterprise Kernel (UEK) to Red Hat's Compatible Kernel (RHCK) as per their Application Development Team requirement.

A week later, it was noticed that new kernels were present on the system, Grub's kernel indexes had changed, and that system had reverted to booting with UEK.


Through the below command, it was observed that RHCK was defined with "index=1":

After rebooting the server, it was confirmed that the system was booting by default with RHCK.

Since then, no further changes were manually made to Grub's configurations.


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