OK.
Let's talk about kernel updates.
If you do a kernel update, dnf update kernel is what you do.
Now, normally, when you update files, the old file is removed
and is replaced with the new file.
If you update the kernel, you get a newer version
of the kernel.
And this newer version of the kernel
is installed besides the old version of the kernel.
Here we can see the new version of the kernel is 6.12.0-55.13.1.
And it's asking if I want to install that.
Well, yes, let's install it.
Now, when I use uname-r, I can see my current kernel version.
And as you can see, there is a difference.
I just installed 55.13.1, and the current kernel is 55.9.1.
Now, in the kernel versions, we have 6.
That's the major and 12.
That is the minor and 0.
That is the subversion.
In the Red Hat policy, during the lifetime of distribution,
this is always fixed.
But Red Hat is applying patches to this kernel.
And the Red Hat patch, well, that is 55.13.1.
And that's what we have just updated to.
Now, if you want to see the result, you need to reboot.
And we are going to see it in GRUB.
So here we have the GRUB boot menu.
As you can see, the new kernel has been added to it.
Now, what is different in updates
is that normally you update the package.
The old version is gone.
But in a kernel case, you might get
in trouble for whatever reason, failing drivers, for instance,
on your new kernel version.
And that is why there's still an option
to boot the old kernel version.
So just boot it, test it, see if it is working.
And if it is working, you're OK.
And then you don't need the old kernel anymore.
No need to remove it.
It's always smart to have a couple of old kernels
as a backup option in case anything fails.