How set kernel on boot for R9.2?

Rocky Linux Tech Help
1

Hi-

I installed KDE and it forced a new kernel install. I want to revert to the older kernel. Uninstalling KDE did not work.

[root@host ~]# uname -a
Linux host.domain.com 5.14.0-427.31.1.el9_4.x86_64 #1 SMP PREEMPT_DYNAMIC Wed Aug 14 16:15:25 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux

[root@host ~]# rpm -q kernel
kernel-5.14.0-284.11.1.el9_2.x86_64
kernel-5.14.0-284.30.1.el9_2.x86_64

[root@host ~]# dnf list --showduplicates kernel
Last metadata expiration check: 2:55:01 ago on Thu 22 Aug 2024 12:45:30 PM PDT.
Installed Packages
kernel.x86_64 5.14.0-284.11.1.el9_2 @anaconda
kernel.x86_64 5.14.0-284.30.1.el9_2 @@commandline
Available Packages
kernel.x86_64 5.14.0-427.31.1.el9_4 baseos

Why is 5.14.0-427.31.1.el9_4.x86_64 reflected in uname if it is not installed? How do I select 5.14.0-284.30.1.el9_2 as the boot kernel? Thank you.

2

I used infos here:

and ran:
grubby --set-default=/boot/vmlinuz-5.14.0-284.30.1.el9_2.x86_64

looks good! please let me know if i missed anything. thank you.

3

Because ‘kernel’ is not everything. In fact, it is very little:

$ dnf -q rq -l kernel-5.14.0-427.31.1.el9_4.x86_64
Package kernel-5.14.0-427.31.1.el9_4.x86_64 contains no files

$ dnf -q rq --requires --resolve kernel-5.14.0-427.31.1.el9_4.x86_64
kernel-core-0:5.14.0-427.31.1.el9_4.x86_64
kernel-modules-0:5.14.0-427.31.1.el9_4.x86_64
kernel-modules-core-0:5.14.0-427.31.1.el9_4.x86_64

So what does?

rpm -qa kernel\*
dnf list kernel\*
dnf rq --installonly

You did set the default entry “in the GRUB” menu that GRUB chooses on boot. For now.
The install of each new kernel(-core) will change that. See /etc/sysconfig/kernel

Kernel 5.14.0-427.31.1.el9_4 contains many security and bug fixes and new features that the 5.14.0-284.30.1.el9_2 do not have nor never will.

There will be no fixes for el9_2. el9_4 is the fix (until el9_5 is released). Rocky supports only latest – currently el9_4 based versions of packages.

If updated application packages start to require newer kernel – like the KDE did – and truly require, then you can’t install/update those either. Particularly GRUB on systems that use Secure Boot belong to that category.

“Want” is an unspecific, weak requirement. Is there a real, concrete, technical reason why use of supported version of Rocky is not possible for you?