VPS & Cloud

How to Install CloudLinux OS on a cPanel/WHM Server

Flyhost Team 09 May 2026 3 views

CloudLinux OS is a hardened Linux distribution designed specifically for shared web hosting. It wraps each cPanel account inside a Lightweight Virtual Environment (LVE) that caps CPU, RAM, I/O, and connection limits — so one noisy tenant can never bring down neighbouring sites.

Why Use CloudLinux on a Shared Hosting Server?

Isolates each account — runaway scripts can't eat shared resources
CageFS hides system files from users, blocking many local exploits
PHP Selector lets each user choose their own PHP version independently
Reduces support tickets and server crashes on oversold servers
Required by many hosting providers for reseller/shared environments

Prerequisites

A server running cPanel & WHM on AlmaLinux 8/9, CentOS 7, or CloudLinux-compatible OS
A valid CloudLinux licence (30-day trial available at cloudlinux.com)
Root SSH access
At least 2 GB RAM

Step 1 — Get Your CloudLinux Activation Key

Sign up at cloudlinux.com, purchase or trial a licence, and copy your activation key from the dashboard. It looks like: 12345678-abcd-efgh-ijkl-1234567890ab

Step 2 — Download and Run the Conversion Script

CloudLinux provides an official conversion script that migrates your existing OS kernel and packages in-place — no reinstall needed:

bash

wget https://repo.cloudlinux.com/cloudlinux/sources/cln/cldeploy
chmod +x cldeploy
sh cldeploy -k YOUR-ACTIVATION-KEY

The script installs the CloudLinux kernel, replaces relevant packages, and sets up the LVE manager. This takes 5–15 minutes.

Step 3 — Reboot Into the CloudLinux Kernel

bash

reboot

After reboot, verify the CloudLinux kernel is active:

bash

uname -r

You should see lve in the kernel name, e.g. 4.18.0-513.24.1.lve.el8.x86_64.

Step 4 — Enable CageFS

CageFS creates a per-user virtualised filesystem so users can't see each other's files:

bash

cagefsctl --init
cagefsctl --enable-all

Step 5 — Install PHP Selector

PHP Selector lets each cPanel user independently pick PHP 7.4, 8.0, 8.1, 8.2, 8.3, etc.:

bash

yum install lvemanager lve-utils alt-php-regexps -y
/usr/bin/cl-selector --setup-host

In WHM, go to CloudLinux > PHP Selector to enable PHP versions and extensions.

Step 6 — Set LVE Limits in WHM

In WHM navigate to CloudLinux > LVE Manager. Set sensible defaults for shared hosting:

CPU: 100–200% (1–2 cores)
RAM (VMEM): 512 MB – 1 GB
I/O: 1024 KB/s
Processes (NPROC): 100

Verifying LVE is Working

bash

lvelist
lveinfo --period=1d --user=username

Conclusion

CloudLinux transforms a standard shared server into a robust, multi-tenant environment. Combined with CageFS and PHP Selector, it dramatically improves security and stability. For any production shared hosting server, CloudLinux is an essential investment.