What is KernelCare?
KernelCare is an optional server add-on product that will allow your server to receive kernel updates without needing to manually download, install, and reboot your system.
The CloudLinux team monitors for kernel updates as they relate to kernels that they support. Then they provision the updates to a distribution server that your server will periodically reach out to. When your KernelCare detects that there is an available patch that’s when the magic happens.
The KernelCare system loads the update into a kernel address space, sets up the relocations by fixing references to original kernel code and data, and then safely switches the execution path from the original code to the updated code blocks.
To apply the update, a special KernelCare kernel module is used. The KernelCare Kernel Module functions by allocating memory in the kernel and then loads the new, secure code into the kernel. It will then freeze the incoming processes momentarily. Next, it takes the original functions, modifies them to utilize the new secure code (where applicable,) and then unfreezes those processes after the ensuring a successful switch from the old code.
All of this happens in seconds and there is no downtime involved with the switch. Your system can now seamlessly utilize the new patch for the kernel. The best part? That was all done automatically. The system can handle its own updates, fully, and stay alive for maximum server uptime.
Note: This is an add-on product that we highly encourage our cPanel/Linux server owners to install to keep their systems up-to-date without lifting a finger.