CloudLinux and CentOS are both Linux operating systems in the Red Hat family, but they serve different purposes. CentOS Linux was a free, general-purpose server system, and it has now reached end of life. CloudLinux OS is a paid system built specifically for shared hosting servers, adding per-account resource limits and isolation so one busy or compromised website cannot drag down or reach the others.
What CentOS is, and what happened to it
CentOS Linux was a free, community-built rebuild of Red Hat Enterprise Linux (RHEL). For many years it was the default operating system for web servers and cPanel servers, because it offered RHEL’s stability without the subscription cost.
That changed when Red Hat moved its focus to CentOS Stream. CentOS Stream is a rolling preview of what will appear in the next RHEL release, rather than a stable rebuild of a released version. CentOS Linux 8 reached end of life at the end of 2021, and CentOS Linux 7 reached end of life on 30 June 2024. Neither receives regular security updates any more.
In practice, this means you should not build a new production server on CentOS Linux. If you still run one, plan a migration.
What CloudLinux OS is
CloudLinux OS is a commercial operating system from CloudLinux, built on the RHEL-compatible base. It is designed for servers where many unrelated customers share the same machine, which is exactly how shared and reseller hosting works. It runs alongside control panels such as cPanel and Plesk.
Its main features are:
- LVE (Lightweight Virtual Environment): sets limits on CPU, memory, disk I/O and concurrent processes for each hosting account. If one site gets a traffic spike or runs a badly written script, it hits its own limit instead of slowing every other site on the server.
- CageFS: gives each user a separate, virtualised view of the file system. Users cannot see other customers’ files or most sensitive system files, which makes it much harder for one compromised account to attack others.
- PHP Selector: lets each account choose its own PHP version and extensions, so an old application and a new one can run on the same server.
- MySQL Governor: monitors and limits database usage per account, so one heavy database cannot monopolise the database server.
CloudLinux OS needs a paid licence per server. It is not a control panel and does not manage billing or clients; it is the operating system layer underneath.
CloudLinux vs CentOS: the key differences
- Purpose: CentOS was a general-purpose server OS. CloudLinux is built for multi-tenant hosting.
- Cost: CentOS was free. CloudLinux needs a paid licence for each server.
- Support status: CentOS Linux 7 and 8 are end of life. CloudLinux OS is actively maintained.
- Resource control: CentOS has standard Linux tools but nothing aimed at per-customer hosting limits. CloudLinux adds LVE and MySQL Governor.
- Isolation: on a standard system, careful configuration is needed to keep hosting users apart. CloudLinux adds CageFS for this.
- Compatibility: both are in the RHEL family, so the same packages, commands and administration skills largely apply.
What to use instead of CentOS today
Since CentOS Linux is end of life, the realistic choice for a new RHEL-family server is usually between:
- AlmaLinux or Rocky Linux: free, community-supported RHEL-compatible distributions that took over the role CentOS used to play. Both are supported by cPanel.
- CloudLinux OS: the paid option when the server will host many separate customers.
- RHEL: for organisations that want a vendor subscription and support.
Ubuntu is also common for servers, especially for developers and container workloads, but it is outside the Red Hat family.
When CloudLinux is worth paying for
CloudLinux makes sense when:
- You run shared hosting or reseller hosting with many customers on one server.
- You host client sites as an agency and want one problem site not to affect the rest.
- You need different PHP versions for different accounts on the same server.
- You want an extra layer of separation between accounts in case one site is hacked.
It is usually not needed when the server runs a single application, a single company’s websites, or a development environment. AlmaLinux or Rocky Linux will do the job without a licence fee.
Migrating away from CentOS
If you still run CentOS Linux 7 or 8, you have a few options:
- Convert in place to AlmaLinux, Rocky Linux or CloudLinux using the conversion tools those projects provide. This can work for some versions, but take a full backup first and test on a copy where possible.
- Build a new server on a supported OS and move sites across. This is often cleaner, especially when moving from CentOS 7, because in-place upgrades across major versions are more complicated.
- Move to managed hosting so the OS is someone else’s job.
For cPanel servers, check cPanel’s current list of supported operating systems before you choose.
Frequently asked questions
Is CloudLinux based on CentOS?
CloudLinux was originally built on CentOS and RHEL. Current versions are built on the RHEL-compatible base, so they remain in the same family and administration works in a similar way.
Is CentOS still safe to use?
CentOS Linux 7 and 8 are end of life and no longer get regular security updates, so they are not a safe choice for internet-facing production servers. Migrate to a supported operating system.
Is CentOS Stream the same as CentOS?
No. CentOS Stream sits just ahead of RHEL and changes continuously. It suits people who want to see upcoming RHEL changes, but many hosting control panels, including cPanel, do not support it.
Do I need CloudLinux on a VPS that hosts only my own sites?
Usually not. Its main benefits are per-account limits and isolation between different customers. For a server you alone use, a free RHEL-compatible system is normally enough.
Next step
If you run a hosting server and want account isolation, see the Tremhost CloudLinux licence page for current pricing. If you would rather not manage the OS yourself, a managed cPanel VPS comes with cPanel and WHM, CloudLinux, LiteSpeed and Imunify360 already set up, and reseller hosting runs on CloudLinux too.
