What CloudLinux adds to cPanel

CloudLinux OS is a version of Enterprise Linux built for shared and reseller hosting. On a cPanel server it adds:

• LVE limits: CPU, memory, I/O and process limits for each account, so one busy site cannot slow the whole server.
• CageFS: each user sees only their own files and a limited view of the system.
• PHP Selector: users choose their own PHP version and extensions.
• CloudLinux Manager in WHM to set limits and see which accounts use the most resources.

It is most useful on servers that host many separate accounts. A server that runs only your own sites may not need it.

Before you install

• ✓ A server running a release that CloudLinux can convert, such as AlmaLinux or Rocky Linux 8 or 9, with cPanel installed.
• ✓ A CloudLinux licence: an activation key, or an IP-based licence bought for the server’s IP address.
• ✓ A full backup or snapshot of the server. The conversion replaces the kernel and many system packages.
• ✓ Console access (VNC or KVM) in case the server does not come back after the reboot.
• ✓ A maintenance window. Sites go down during the reboot.

Step 1: update and back up

dnf update -y

# Back up every cPanel account to /home (needs enough free space)
for u in $(ls /var/cpanel/users); do /scripts/pkgacct "$u"; done

Copy the backups off the server as well. See our cPanel backup and restore guide.

Step 2: run the conversion

cd /root
wget https://repo.cloudlinux.com/cloudlinux/sources/cln/cldeploy

# With an activation key
sh cldeploy -k YOUR_ACTIVATION_KEY

# Or, with an IP-based licence
sh cldeploy -i

Run it inside screen, so a dropped SSH connection does not stop it. The script replaces the system packages and installs the CloudLinux kernel. It can take a while.

Step 3: reboot and check

reboot

# After logging back in
cat /etc/redhat-release     # should name CloudLinux
uname -r                    # should show a kernel with "lve" or "el" and CloudLinux in the name
cagefsctl --cagefs-status   # CageFS status

In WHM, open CloudLinux Manager to check the default limits.

Step 4: set up limits, CageFS and PHP Selector

1. In CloudLinux Manager, set default limits for each hosting package. Start generous, then lower them as you learn how accounts behave.
2. Turn on CageFS for all users, then add exceptions only where needed.
3. Configure PHP Selector: choose the default version and the extensions users may enable.
4. Watch the usage reports for a few days and adjust the limits.

See our guide to PHP Selector on CloudLinux.

Removing CloudLinux

Removing CloudLinux is not as simple as installing it. The kernel, the system packages and cPanel’s integration all change. CloudLinux has documented an uninstall option in cldeploy, but the steps and support depend on the CloudLinux version. You have two options:

Option A: move to a fresh server (recommended)

1. Set up a new server with AlmaLinux and cPanel. See our cPanel install guide.
2. Use WHM > Transfers > Transfer Tool to copy all accounts from the CloudLinux server.
3. Test the sites, change DNS, and keep the old server until everything has run cleanly for a few days.
4. Cancel the CloudLinux licence once the old server is shut down.

This avoids leftover packages and gives you a clean system.

Option B: uninstall in place

Only try this with a full backup or snapshot, console access, and CloudLinux’s current uninstall instructions for your version. Before you start, turn off CageFS and remove PHP Selector settings that sites rely on. If anything goes wrong, restore the snapshot. When in doubt, ask CloudLinux support or our team first.

Troubleshooting