The Linux Kernel ::

Find out the installed kernel packages:

user1@localhost:~$ rpm -qa *kernel*
kernel-modules-extra-matched-6.12.0-124.8.1.el10_1.x86_64
kernel-tools-libs-6.12.0-124.8.1.el10_1.x86_64
kernel-modules-core-6.12.0-124.8.1.el10_1.x86_64
kernel-core-6.12.0-124.8.1.el10_1.x86_64
kernel-modules-6.12.0-124.8.1.el10_1.x86_64
kernel-modules-extra-6.12.0-124.8.1.el10_1.x86_64
kernel-tools-6.12.0-124.8.1.el10_1.x86_64
kernel-6.12.0-124.8.1.el10_1.x86_64
user1@localhost:~$

Find out the kernel version and release:

user1@localhost:~$ uname --help
Usage: uname [OPTION]...
Print certain system information.  With no OPTION, same as -s.

  -a, --all                print all information, in the following order,
                             except omit -p and -i if unknown:
  -s, --kernel-name        print the kernel name
  -n, --nodename           print the network node hostname
  -r, --kernel-release     print the kernel release
  -v, --kernel-version     print the kernel version
  -m, --machine            print the machine hardware name
  -p, --processor          print the processor type (non-portable)
  -i, --hardware-platform  print the hardware platform (non-portable)
  -o, --operating-system   print the operating system
      --help        display this help and exit
      --version     output version information and exit

GNU coreutils online help: <https://www.gnu.org/software/coreutils/>
Full documentation <https://www.gnu.org/software/coreutils/uname>
or available locally via: info '(coreutils) uname invocation'
user1@localhost:~$ 
user1@localhost:~$ uname -v
#1 SMP PREEMPT_DYNAMIC Fri Oct 17 13:03:58 EDT 2025
user1@localhost:~$ uname -r
6.12.0-124.8.1.el10_1.x86_64
user1@localhost:~$

in the /boot directory#

With the exception of the efi and grub2 directories, which deal with the bootloader for UEFI and BIOS systems respectively, the rest of the files and subdirectories under the /boot/ directory are related to the kernel.

At a minimum, there is an active kernel and a rescue kernel on a fresh-installed RHEL; To each of them corresponds an initramfs file, a configuration file under /boot/loader/entries/ and a monolithic compressed package whose name starts with vmlinuz. The files related to the rescue kernel are referenced by the word rescue in their names:

user1@localhost:~$ ls /boot
config-6.12.0-124.8.1.el10_1.x86_64
efi
grub2
initramfs-0-rescue-10e1d369baf34f8e83ef5ce0cf67aad2.img
initramfs-6.12.0-124.8.1.el10_1.x86_64.img
initramfs-6.12.0-124.8.1.el10_1.x86_64kdump.img
loader
symvers-6.12.0-124.8.1.el10_1.x86_64.xz
System.map-6.12.0-124.8.1.el10_1.x86_64
vmlinuz-0-rescue-10e1d369baf34f8e83ef5ce0cf67aad2
vmlinuz-6.12.0-124.8.1.el10_1.x86_64
user1@localhost:~$

The /boot/loader/entries contains configuration files for the kernels:

user1@localhost:~$ ls -l /boot/loader/entries
ls: cannot open directory '/boot/loader/entries': Permission denied
user1@localhost:~$ sudo ls -l /boot/loader/entries
[sudo] password for user1: 
total 8
-rw-r--r--. 1 root root 498 May 25 19:07 10e1d369baf34f8e83ef5ce0cf67aad2-0-rescue.conf
-rw-r--r--. 1 root root 460 May 25 19:07 10e1d369baf34f8e83ef5ce0cf67aad2-6.12.0-124.8.1.el10_1.x86_64.conf
user1@localhost:~$

The name of each configuration file starts with the machine ID; The value of the machine ID is found in /etc/machine-id:

user1@localhost:~$ ls /etc/machine-id
/etc/machine-id
user1@localhost:~$

Sample content of the configuration file of the active kernel:

user1@localhost:~$ sudo cat /boot/loader/entries/10e1d369baf34f8e83ef5ce0cf67aad2-6.12.0-124.8.1.el10_1.x86_64.conf
[sudo] password for user1: 
title Red Hat Enterprise Linux (6.12.0-124.8.1.el10_1.x86_64) 10.1 (Coughlan)
version 6.12.0-124.8.1.el10_1.x86_64
linux /vmlinuz-6.12.0-124.8.1.el10_1.x86_64
initrd /initramfs-6.12.0-124.8.1.el10_1.x86_64.img $tuned_initrd
options root=/dev/mapper/rhel-root ro crashkernel=2G-64G:256M,64G-:512M resume=UUID=1b78a569-98e2-4c07-95c6-fdd850456cf2 rd.lvm.lv=rhel/root rd.lvm.lv=rhel/swap rhgb quiet 
grub_users $grub_users
grub_arg --unrestricted
grub_class rhel
user1@localhost:~$

The Linux Kernel

Kernel-related files#

in the /boot directory#