8.1. Upgrading to Linux Kernel 5.4 or Later

In the Linux kernel version 5.3 or earlier, LOCKSS at startup might block [1] or hang [2] due to lack of entropy [3] in the Linux environment. Mitigation of this problem first appeared in Linux kernel version 5.4 [4]. Therefore, Linux kernel 5.4 or later is required to run LOCKSS. Most versions of the Compatible Operating Systems satisfy this requirement out of the box. This section describes how to upgrade certain operating systems to Linux kernel 5.4 or later.

Tip

Upgrading to Linux kernel 5.4 or later is expected to be needed for some operating systems in the in the RHEL 8 family (AlmaLinux OS 8, Oracle Linux 8, Red Hat Enterprise Linux (RHEL) 8, and Rocky Linux 8).

You can check the Linux kernel version by typing:

uname --kernel-release

at the host's console.

  • If version 5.4 or later is output, then the host satisfies the Linux kernel version requirement.

  • If version 5.3 or earlier is output, then the host does not satify the Linux kernel version requirement.

If an upgrade to Linux kernel version 5.4 or later is required, select your operating system below, and if applicable select the particular version of your operating system, then follow the instructions accordingly:

If an upgrade to Linux kernel 5.4 or later is required for this operating system, you will need to install a kernel from the ELRepo Project. Follow these steps (as root):

  1. First, this method will only work with hosts with a x86_64 architecture. Type this command:

    uname --machine

    • If the output is different from x86_64, then this kernel update method will not work. Please contact us for further assistance.

    • If the output is x86_64, then proceed to the next step.

  2. Import the ELRepo Project GPG keys with these two rpm commands (as root):

    rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org

rpm --import https://www.elrepo.org/RPM-GPG-KEY-v2-elrepo.org

    Reference: https://elrepo.org/wiki/doku.php?id=start#get_started

  3. Install the elrepo-release package for RHEL 8 with this yum command (as root):

    yum install https://www.elrepo.org/elrepo-release-8.el8.elrepo.noarch.rpm

    Reference: https://elrepo.org/wiki/doku.php?id=start#get_started

  4. Install the kernel-ml package from the elrepo-kernel channel with this dnf command (as root):

    dnf  --enablerepo=elrepo-kernel --refresh install kernel-ml

    Reference: https://elrepo.org/wiki/doku.php?id=kernel-ml

  5. Reboot the host.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

Section last updated:

2026-04-02

If an upgrade to Linux kernel 5.4 or later is required for this operating system, you will need to install the Unbreakable Enterprise Kernel Release 6 Update 3 (UEK R6U3) from the Unbreakable Linux Network (ULN). Follow these steps:

  1. In your ULN account, select your host, then select System Details ‣ Manage Subscriptions, then subscribe to the ol8_x86_64_baseos_latest and ol8_x86_64_UEKR6 channels.

    Reference: "Subscribing to ULN Channels" at https://docs.oracle.com/en/operating-systems/uek/6/relnotes6.3/uek6-InstallationandAvailability.html#ol_sub_uln

  2. At the host's console, run the following dnf command (as root):

    dnf config-manager --enable ol8_baseos_latest ol8_addons ol8_UEKR6

    to enable the ol8_baseos_latest, ol8_addons, and ol8_UEKR6 repositories.

    Reference: "Enabling Access to Oracle Linux Yum Server Repositories" at https://docs.oracle.com/en/operating-systems/uek/6/relnotes6.3/uek6-InstallationandAvailability.html#ol_sub_pubyum

  3. Then update your system with this dnf command (as root):

    dnf update

    Reference: "Upgrading Your System" at https://docs.oracle.com/en/operating-systems/uek/6/relnotes6.3/uek6-InstallationandAvailability.html#ol_upgradea_sys

  4. Reboot the host.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

If an upgrade to Linux kernel 5.4 or later is required for this operating system, you will need to install a kernel from the ELRepo Project. Follow these steps (as root):

  1. First, this method will only work with hosts with a x86_64 architecture. Type this command:

    uname --machine

    • If the output is different from x86_64, then this kernel update method will not work. Please contact us for further assistance.

    • If the output is x86_64, then proceed to the next step.

  2. Import the ELRepo Project GPG keys with these two rpm commands (as root):

    rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org

rpm --import https://www.elrepo.org/RPM-GPG-KEY-v2-elrepo.org

    Reference: https://elrepo.org/wiki/doku.php?id=start#get_started

  3. Install the elrepo-release package for RHEL 8 with this yum command (as root):

    yum install https://www.elrepo.org/elrepo-release-8.el8.elrepo.noarch.rpm

    Reference: https://elrepo.org/wiki/doku.php?id=start#get_started

  4. Install the kernel-ml package from the elrepo-kernel channel with this dnf command (as root):

    dnf  --enablerepo=elrepo-kernel --refresh install kernel-ml

    Reference: https://elrepo.org/wiki/doku.php?id=kernel-ml

  5. Reboot the host.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

If an upgrade to Linux kernel 5.4 or later is required for this operating system, you will need to install a kernel from the ELRepo Project. Follow these steps (as root):

  1. First, this method will only work with hosts with a x86_64 architecture. Type this command:

    uname --machine

    • If the output is different from x86_64, then this kernel update method will not work. Please contact us for further assistance.

    • If the output is x86_64, then proceed to the next step.

  2. Import the ELRepo Project GPG keys with these two rpm commands (as root):

    rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org

rpm --import https://www.elrepo.org/RPM-GPG-KEY-v2-elrepo.org

    Reference: https://elrepo.org/wiki/doku.php?id=start#get_started

  3. Install the elrepo-release package for RHEL 8 with this yum command (as root):

    yum install https://www.elrepo.org/elrepo-release-8.el8.elrepo.noarch.rpm

    Reference: https://elrepo.org/wiki/doku.php?id=start#get_started

  4. Install the kernel-ml package from the elrepo-kernel channel with this dnf command (as root):

    dnf  --enablerepo=elrepo-kernel --refresh install kernel-ml

    Reference: https://elrepo.org/wiki/doku.php?id=kernel-ml

  5. Reboot the host.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

This operating system is not expected to require an upgrade of the Linux kernel to version 5.4 or later.

Footnotes