In my previous article, I described what KernelCare is. In this article, I’m going to tell you how to install, uninstall, clear the KernelCare cache, and other important information regarding KernelCare. In case you’re yet to know about the product, here’s a short recap. KernelCare provides automated security updates to the Linux kernel. It offers patches and error fixes for various Linux kernels.

So, if you are looking for anything similar, you have landed upon the right page. Let’s begin without further ado.

Prerequisites to Install KernelCare

Before installing KernelCare in your Linux system, ensure that you have either of these operating systems as given below.

  • 64-bit RHEL/CentOS 5.x, 6.x, 7.x

  • CloudLinux 5.x, 6.x

  • Virtuozzo/PCS/OpenVZ 2.6.32

  • Debian 6.x, 7.x

  • Ubuntu 14.04

Note: In case you have KernelCare installed on your machine, it might be useful to know the current KernelCare version before installing KernelCare next time. To know the current version run the below-given command as root:

/usr/bin/kcarectl –uname

Checking Kernel’s Compatibility with KernelCare

To check if your current kernel is compatible with KernelCare, you need to use the following code.

curl -s -L | python

Installing KernelCare

Run the following command to install KernelCare.

curl -s -L | bash

If you use an IP-based license, you don’t need to do anything more. However, if you use a key-based license, run the following command.

/usr/bin/kcarectl --register KEY

KEY is a registration key code string. It’s given to you when you sign up to purchase or to go through a trial of KernelCare. Let’s see an example.

[[email protected]:~]/usr/bin/kcarectl --register XXXXXXXXXXX

Server Registered

The above example shows a registration key code string.

If you experience a “Key limit reached” error message, then you need to first unregister the server after the trial ends. To do the same type:

kcarectl --unregister

Checking If the Patches Applied Successfully

For checking if the patches have been applied successfully or not, use the command as given below.

/usr/bin/kcarectl --info

Now the software will check for new patches automatically every 4 hours.

If you want to run updates manually, run:

/usr/bin/kcarectl --update

Updating KernelCare Agent

For updating the KernelCare agent package to its latest version available, run:

dnf install -y kernelcare

This command is used for rpm-based distributions including RedHat, CentOS, etc. If you own an apt-based distribution, such as Debian, Ubuntu, etc, you need to type and run the following command.

apt-get install kernelcare

Clearing KernelCare Cache

For clearing the KernelCare cache, you need to run the code given below.

rm -rf /var/cache/kcare/patches echo 1 > /proc/sys/vm/compact_memory echo 3 > /proc/sys/vm/drop_caches kcarectl –update

Uninstalling KernelCare

If experiencing any error, you might want to uninstall KernelCare from your system. To uninstall the package, run this command given below as root.

yum remove kernelcare

Disabling KernelCare Automatic Updates

Once enabling automatic updates for KernelCare, if at any time, you want to disable the KernelCare automatic updates, run the following command.



From this article, you came to know about how to install and uninstall KernelCare on your system. We also learned about prerequisites of installing KernelCare, how you can disable automatic updates, how to check for the new and applied patches, how to clear KernelCare cache, and how you can be a KernelCare agent. It’s recommended to check your kernel’s compatibility with KernelCare before installing the product. You can easily follow the given procedure to check the compatibility. I hope you find this article useful.

Posted by Contributor