How to update Linux Kernel without rebooting?

#CloudLinux KernelCare #Download and install KernelCare #How to install KernelCare #How to install Kpatch #install Ksplice #Kpatch #Ksplice #Linux kernel live patching #Oracle Ksplice #Rebootless Linux kernel updates #update Linux Kernel without rebooting #update Linux without rebooting

Patching an always-on or high-availability Linux Kernel without rebooting is very important for continuous processes. Here are some methods of live security updates you can use.

Applying Linux Kernel updates can be a problem, especially if you are working with an always-on or high-availability system, which should be operative all the time. But we also know that security experts are discovering new vulnerabilities and bugs in Kernel frequently and most of them are almost immediately patched shortly after.

But applying the patch may also require you to reboot the system which causes the system to go offline for a certain amount of time. Since patches are extremely critical for the system’s safety, the best solution is to apply the automatic patches without rebooting the system with these methods:

5 solutions to patch Linux Kernel without a reboot

There are several methods allows you to apply kernel security patches without rebooting. Rebootless Linux kernel updates are also called as Linux kernel live patching or live update. Rebootless Kernel updates are not a replacement for full kernel upgrades but it allows you to patch critical security vulnerabilities and bug fixes. With these methods, you can keep your servers safe and running without outage for years.

Several Linux vendors offer rebootless kernel updates. Your solution mostly depends on the distribution you are running. Here are the 5 solutions to update Linux kernel without reboot:

CloudLinux KernelCare

kernercare logo - How to update Linux Kernel without rebooting?

KernelCare, developed by CloudLinux, was launched in 2014. KernelCare covers most of the popular distributions, including CentOS, RHEL, Oracle Linux, Debian, Ubuntu, and others. KernelCare also supports the older 2.6.32 kernels from RHEL 6. KernelCare is an “install and forget” solution with easy installation. After the installation, it downloads and applies the kernel patches automatically without rebooting.

READ ALSO HERE :  Red Hat Enterprise Linux (RHEL) 7.8 is out

KernelCare’s ability to handle more complex patches for vulnerabilities such as Zombiload, Meltdown and Spectre, and Mutagen Astronomy makes it better than its competitors. It also offers custom and fixed-date patching to meed the specific needs. CloudLinux also offers support for KernelCare with its experienced support team.

🙂 Pros: Easy install. No reboot required. Wide OS coverage (including one of the most popular Linux flavors, Ubuntu). Supports custom and fixed-date patching. Good support and industry know-how from CloudLinux.

😐 Cons: Commercial (but there is a free, 30-day trial). There is also a free KernelCare license for non-profit organizations.

  • Click here to try KernelCare free for 30 days.
  • Click here to get a free license for your non-profit organization.

How to install KernelCare ?

To install KernelCare use the following commands on the command line:

Step 1: Download and install KernelCare using wget or curl

wget -qq -O - | bash


curl -s -L | bash

Step 2: Register the key:

sudo /usr/bin/kcarectl -register <your key>


kcarectl –register <your key>

Step 3: To check if the running kernel is supported by KernelCare:

wget -qq -O – | python


curl -s -L | python

Oracle Ksplice

ksplice logo - How to update Linux Kernel without rebooting?

Ksplice is the oldest rebootless kernel updating solution. It is lates acquired by the Oracle and now it only supports Oracle Linux and RedHat Enterprise Linux distributions and an Oracle license is needed for the deployment. It requires running the install script once in the server and then it applies the patches automatically. It lacks an important feature such as scheduling.

READ ALSO HERE :  Minimum PHP recommendation for WordPress is 7.2

🙂 Pros: Automatic updates. No reboot required.

😐 Cons: Only for Oracle distributions. Requires a support license.

How to install Oracle Ksplice?

To install Oracle Ksplice use the following commands on the command line:

Step 1: Download Oracle Ksplice using wget

sudo wget -N

Step 2: Install Ksplice

sudo sh install-uptrack-oc -autoinstall

Red Hat Kpatch

red hat logo - How to update Linux Kernel without rebooting?

Red Hat Kpatch is Red Hat’s own rebootless kernel live patching tool. It was announced in 2014. It can be ported to work on Fedora and CentOS and Debian-based systems such as Ubuntu and Gentoo. Unlike other solutions in the list, it doesn’t apply the patches automatically and the administrator should check and apply the patches manually.

🙂 Pros: No reboot required.

😐 Cons: Not automated. Limited distributions.

How to install Red Hat Kpatch?

To install Red Hat Kpatch use the following commands on the command line:

Step 1: Download Kpatch using yum

sudo yum install kpatch

Step 2: Install Kpatch

sudo yum install kpatch-patch-X.X.X.el7.x86_64.rpm

Canonical Livepatch

ubuntu logo - How to update Linux Kernel without rebooting?

Livepatch is the Canonical’s, the developer behind the Ubuntu distribution, solution for live patching kernels. It is free for up to 3 machines for Ubuntu Community members. Unlike other solutions in the list, it allows administrators to create their own patches but it can be difficult and time-consuming work. Livepatch is available for Ubuntu 16.04 and later, and RHEL 7.x.

READ ALSO HERE :  You Can Download Kali Linux 2020.2 Now !

🙂 Pros: Automatic kernel updates. No reboot required.

😐 Cons: Non-trivial custom kernel patches. Limit to the number of updatable hosts (additional hosts for a fee).

How to install Canonical Livepatch?

To install Canonical Livepatch use the following commands on the command line:

Step1: Get your Livepatch token

Get your Livepatch token here first

Step 2: Install Livepatch using snap

sudo snap install canonical-livepatch

Step 3: Enable Livepatch using Token

sudo canonical-livepatch enable [TOKEN]

SUSE Kgraft

suse logo - How to update Linux Kernel without rebooting?

SUSE’s Kgraft live patching solution only supports SUSE’s own Linux Enterprise Server 12 and it comes preinstalled with the distribution. Thus it requires no additional installation. It follows a different principle to most other approaches but it’s feature-set is comparable to Kpatch.

🙂 Pros: No installation needed. No reboot required.

😐 Cons: Single platform support. Commercial (but there is a generous 60-day free trial).

How to install SUSE Kgraft?

There is no need to install SUSE Kgraft. It comes installed in SUSE Linux Enterprise Server 12.