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CloudLinux ​

Where to find it in the panel: the CloudLinux module page is at /admin/modules/cloudlinux, and LVE Manager and the Isolation Report are under Settings > CloudLinux.

CloudLinux improves stability, density, and security on shared hosting by isolating each account and controlling its resources. AdminBolt converts your server to CloudLinux through a guided, staged installer, then exposes CloudLinux features directly in the panel: per-account resource limits on hosting plans, unified PHP versions across three repositories, and the native LVE Manager UI embedded in the admin panel.

What it provides ​

  • LVE resource isolation - per-account limits on CPU, memory, I/O, IOPS, processes, and entry processes, so a single account cannot exhaust the node.
  • PHP selector - per-account PHP version selection, including legacy Alt-PHP versions down to PHP 5.2.
  • CageFS - per-account filesystem isolation that keeps accounts from seeing each other. Installed when you complete the LVE Manager setup wizard (see Install LVE Manager).
  • Hardened kernel - the CloudLinux kernel with the security and stability improvements the platform is built on.
  • Guided installer - a staged wizard that validates your key, converts the OS, reboots, and confirms the result.
  • Panel integration - resource limits on hosting plans and resellers, a unified Settings > PHP > PHP Versions page, the embedded LVE Manager, a CageFS switch per account, and an Isolation Report that checks the server keeps its accounts apart.

Before you start ​

  • Your server runs a supported OS: AlmaLinux 9 or Rocky Linux 9, which converts to CloudLinux 9.
  • You have a valid CloudLinux activation key (API key). An empty key runs an IP-based check only, which is not enough to install.
  • You are signed in to the admin panel. Converting to CloudLinux is a node-level action and is admin-only.
  • You have taken a provider snapshot of the server before you begin.

Converting to CloudLinux rewrites the operating system and requires a reboot. The conversion is effectively irreversible, and it interrupts active sessions and services on the node. Take a provider snapshot first, and plan the change for a quiet moment.

Install CloudLinux ​

The installer is a staged wizard with the steps Validate, Install, LVE Manager, and Manage. It has no sidebar entry of its own: open Modules in the sidebar and click the CloudLinux card, which opens the installer at /admin/cloudlinux-installer.

Once the conversion is done, CloudLinux is managed on Settings > CloudLinux > LVE Manager (/admin/settings/cloudlinux-lvemanager).

1. Validate your activation key ​

  1. Enter your CloudLinux activation / API key.
  2. Click Validate.

An empty key runs an IP-based validation, but that does not unlock the install - a valid activation key is required. On success, step 1 turns green and Install CloudLinux unlocks.

2. Install CloudLinux ​

  1. Click Install CloudLinux and confirm in the dialog.
  2. The panel converts the operating system in the background, streams the live deploy log from /var/log/cldeploy.log, and shows the state converting.

This step converts the OS and is effectively irreversible. The server reboots as part of the process, and active sessions and services are interrupted, so make sure your snapshot is in place before you confirm.

3. Reboot onto the CloudLinux kernel ​

When the conversion finishes, the state becomes installed-pending-reboot ("CloudLinux installed - reboot required"). Click Reboot now and confirm. The server reboots onto the CloudLinux kernel, with about one to two minutes of downtime.

4. Confirm the conversion ​

After the reboot, the installer shows the state converted ("CloudLinux is already installed"), with an Open LVE Manager button. Your server now runs CloudLinux.

Since panel 1.9.0, the installer page then points to the Isolation Report with Open Isolation Report. Open it next: it says what is still needed before every account is kept apart, including moving the websites to CloudLinux alt-php, and takes the steps it can for you.

If the conversion fails ​

Since panel 1.9.0 a conversion is judged by what ended up on the server: the components the licence edition should bring, and whether the server will boot into CloudLinux.

  • A failed precheck names the reason before the conversion starts, and a conversion that fails names its reason too.
  • On failure, the installer page lists the missing components next to the edition, shows CloudLinux's own log below the conversion log, and explains known causes in plain words, such as an IP address without a licence, with the step that resumes the run.
  • After Try again, the page keeps the previous failed run with its outcome, stage, edition, running kernel, and log.
  • The conversion can also be run again through the admin API on a server that already runs CloudLinux, for example to repair it.

After the conversion ​

Since panel 1.9.0 a conversion leaves Apache set up the way AdminBolt hosting accounts expect. Existing sites keep serving their pages and PHP, and new hosting accounts and domains can be created on the plans the server supports. The setup survives a re-run of the conversion and CloudLinux updates to its Apache packages. The conversion result in the admin API shows whether Apache is ready for AdminBolt accounts.

Install LVE Manager ​

After conversion, the LVE Manager web UI is installed on demand. Open Settings > CloudLinux > LVE Manager (/admin/settings/cloudlinux-lvemanager); the page shows Install LVE Manager to continue. Click Install and confirm - it runs in the background.

Once installed, the native CloudLinux LVE Manager UI is embedded in the panel. Use it for per-user resource usage, statistics, selectors, and CageFS. On first open, CloudLinux shows its own setup wizard, which installs and initializes CageFS and enables the CloudLinux end-user PHP Selector.

Do not skip the CloudLinux setup wizard if you want CageFS. Skipping it leaves CageFS not installed, and AdminBolt does not add it automatically later. Per-account PHP versions still work without CageFS, but per-user CageFS isolation and the end-user PHP Selector stay off until you re-run the wizard. The Isolation Report shows whether CageFS is installed.

Every website inside LVE and CageFS ​

Since panel 1.9.0, websites on a CloudLinux server run CloudLinux alt-php, which runs inside the account's LVE and CageFS, so a website's PHP gets the account's resource limits and cannot see other accounts' files.

  • Hosting plans, domains, and clients choose only from alt-php versions on such a server.
  • A plan or domain set to another PHP release gets the installed alt-php version of the same release.
  • PHP Versions marks Remi PHP and LSPHP as Not supported on CloudLinux and installs only alt-php. A version that is already installed can still be removed.
  • Websites on alt-php and LSPHP keep PHP error messages from visitors by default, also on servers updated to 1.9.0. A domain's own error display setting still applies.

Websites that already run on Remi PHP, LSPHP, or PHP-FPM, for example since before the conversion, keep running on it until you move them. The Isolation Report lists them and moves them to alt-php, and while any are left, the Health page raises a critical issue with their number.

PHP selectors and versions ​

After conversion, Settings > PHP > PHP Versions unifies three repositories on one page: REMI, LiteSpeed (LSPHP), and CloudLinux (Alt-PHP). In our test this listed 30 versions in total - 7 from REMI, 7 from LiteSpeed, and 16 from CloudLinux, including legacy versions down to PHP 5.2. Filter the list by repository to focus on one source.

Filtering by the CloudLinux repository shows the alt-php versions, which is where the legacy PHP versions come from. Since panel 1.9.0, only these can be installed on a CloudLinux server.

Since panel 1.9.0 the panel's list of installed PHP versions, which domains and hosting plans choose from, updates on its own when PHP versions, including alt-php builds, are installed or removed, also when that happens from the command line. A newly installed alt-php version can be assigned straight away, and a removed version drops out of the list. This also applies to servers updated to 1.9.0.

The PHP Selector and the panel ​

Since panel 1.9.0 the panel follows the CloudLinux PHP Selector in LVE Manager:

  • PHP versions enabled or disabled in the PHP Selector appear in or leave the panel's PHP version lists within a minute.
  • An account's command-line PHP, for SSH sessions and cron jobs, follows the PHP version of its main domain, and stays aligned when that version or the account's CageFS setting changes.
  • Extensions switched on or off in the PHP Selector apply to the accounts on that PHP version, and show as the matching settings of that PHP version in the panel.

PHP for new accounts and domains ​

Since panel 1.9.0, new accounts and domains on a converted server, including those created from a backup import, get a PHP version that runs. When a hosting plan's PHP version cannot be served on the server, the create-account form flags the plan with PHP not available on this server as soon as it is picked, and creation is refused with the reason before anything is created. Clients pick only from the PHP versions they are allowed.

WordPress on alt-php ​

Since panel 1.9.0 the WordPress tools work on CloudLinux sites running alt-php: the Install WordPress wizard, the plugin list and plugin removal, site statistics, the version check, and single sign-on. When WP-CLI cannot run, the action names the reason, such as a missing PHP extension or an unavailable PHP version. A management action that fails is reported as failed, and the Overview tab of WordPress management shows which WP-CLI version manages the site.

For how versions are installed and assigned, see PHP Versions.

Per-account resource limits ​

After conversion, editing a hosting plan gains a Resource Limits tab. Open Customers > Hosting Packages > Plans, edit a plan, then open its Resource Limits tab, to set the LVE limits applied to every account on that plan:

  • CPU Speed (%)
  • Physical Memory (MB)
  • Virtual Memory (MB)
  • I/O Throughput (KB/s)
  • IOPS
  • Processes (NPROC)
  • Entry Processes (EP)

Empty fields inherit the platform default. These values map to CloudLinux LVE packages applied to every account on the plan.

Since panel 1.9.0:

  • Clearing limit fields on a plan removes those limits from its accounts, and clearing all of them returns the accounts to the CloudLinux defaults.
  • Processes must be greater than Entry Processes plus 15, counting the CloudLinux default when Entry Processes is empty. The plan form and the admin and reseller hosting plan APIs refuse a smaller value and name the smallest one that works; over the API the answer is 422. An account import raises the value to that minimum.

For how plans are created and assigned, see Hosting Plans.

Limits for resellers and single accounts ​

Since panel 1.9.0:

  • The reseller form has CloudLinux LVE Resource Limits: a CPU, memory, I/O, and process ceiling for all of the reseller's accounts together, which applies alongside each account's plan limits. See Reseller Accounts.
  • Edit Account has CloudLinux LVE Resource Overrides, which replace the plan's limits for one account, still within its reseller's ceiling.
  • Resellers get LVE Usage and LVE Faults under Hosting Management, for their own accounts only. See LVE Usage and LVE Faults.
  • The reseller dashboard and the admin reseller list show the figures for each LVE limit that is set.
  • A System Notifications event for LVE faults on reseller accounts, off by default, alerts the administrator and the reseller. See System Notifications.

When CloudLinux does not take a reseller's new limits, saving the reseller names the accounts that kept their previous limits, and saving again retries.

CageFS per account ​

Since panel 1.9.0 the admin Edit Account form has an Account isolation (CageFS) switch. It shows the account's CageFS state as the server holds it, read each time the form opens, and saving applies a change. When that state cannot be read, the switch is locked and saving leaves CageFS as it is. Switching SSH access off leaves the account in CageFS. Resellers do not see the switch. See Hosting Accounts.

The Isolation Report lists every account outside CageFS and puts them all in with one step.

What clients see ​

  • PHP Selector - since panel 1.9.0, clients find PHP Selector under Advanced in the client panel when LVE Manager is installed, you have not ticked Hide PHP Selector in LVE Manager, and the hosting plan includes the PHP Selector feature. When any of these is missing, the entry is hidden and the page cannot be opened through a direct link either.
  • Embedded CloudLinux screens - they open in a frame sized to the browser window, and longer content, such as AccelerateWP, scrolls inside that frame.
  • Resource Usage options - customers with access to Resource Usage can open its Options tab and see the resource usage notification settings for their account, together with their reseller and plan, without any details from other accounts. The client-area CloudLinux pages that list the available PHP versions open for customers as well.
  • Errors - when a CloudLinux tool behind a client page fails (Resource Usage, X-Ray, PHP Selector, or AccelerateWP), the client sees one neutral message and the panel log records one error entry with the details for you. A tool that prints a warning next to valid data works normally.
  • Ruby applications - since panel 1.9.0, Application Runtimes finds the installed CloudLinux alt-ruby versions, so customers choose their Ruby version on the Applications page.

Coexistence with LiteSpeed ​

CloudLinux and LiteSpeed work together. After conversion, the active web server (Apache, LiteSpeed, or OpenLiteSpeed) is unchanged. Existing domains keep their PHP engine until you move them to alt-php from the Isolation Report. If you also run LiteSpeed, see LiteSpeed for how the two fit together.

Who can do what ​

  • Admin - validates the activation key, converts the server to CloudLinux, reboots, installs the LVE Manager, sets per-plan, per-reseller, and per-account resource limits, switches CageFS per account, and works through the Isolation Report. Converting the server, installing the LVE Manager, setting a reseller's LVE ceiling, switching CageFS, and the Isolation Report are admin-only.
  • Clients - choose the PHP version for their domains and use the language selectors. The version list includes the CloudLinux Alt-PHP versions once conversion is done.
  • Resellers - manage hosting plans and accounts, which inherit the resource limits set on their plans, within the reseller's own LVE ceiling. On their own accounts they can also set CloudLinux LVE Resource Overrides from Edit Account, still within that ceiling. They see LVE Usage and LVE Faults for their own accounts. They do not convert the server, install the LVE Manager, set their own LVE ceiling, or change CageFS.

Admin API ​

The conversion can be driven through the admin API as well; see the API Reference. Since panel 1.9.0:

  • CloudLinux operations answer with job_id for an install or a reboot, and with log for the log endpoints. Integrations that read the agent block of these responses need to read these fields instead.
  • GET /api/admin/cloudlinux/status adds previous_runs and running_kernel.
  • GET /api/admin/cloudlinux/clcustomizer-log and GET /api/admin/cloudlinux/clcustomizer-log/previous return CloudLinux's own log for the current and the previous conversion run.
  • A failed POST /api/admin/runtimes/app-server/{runtime}/enable answers 502 with a correlation_id to quote to support.

Troubleshooting ​

  • Install CloudLinux stays locked - an IP-based validation (empty key) does not unlock the install. Enter a valid CloudLinux activation key and click Validate so step 1 turns green.
  • CloudLinux features do not appear after conversion - the conversion only takes effect after a reboot. Complete the Reboot now step so the server boots onto the CloudLinux kernel and the state reads converted.
  • LVE Manager shows "Install LVE Manager to continue" - the LVE Manager web UI is installed on demand after the reboot. Open Settings > CloudLinux > LVE Manager, click Install, and wait for the background install to finish.
  • Resource Limits tab is missing on a hosting plan - the tab appears after the server is converted to CloudLinux. Confirm the installer shows the converted state, then reopen the plan under Customers > Hosting Packages > Plans.
  • A client page for a CloudLinux tool shows a general error - the details are in the panel log, one entry per failure. See What clients see.
  • X-Ray or AccelerateWP refuses to install - both need a CloudLinux OS Shared Pro license. On another license edition the install is refused and names the edition; change the license, then install again.
  • Websites still run PHP outside LVE and CageFS - open the Isolation Report and use Move websites to alt-php.
  • A conversion failed - read the missing components and the known cause on the installer page, fix the cause, and use the step it names to resume. See If the conversion fails.
  • PHP versions work but CageFS is not installed - this is expected if you skipped the CloudLinux setup wizard. Per-account PHP versions work without CageFS, but per-user isolation and the end-user PHP Selector stay off. Re-run the setup wizard in the LVE Manager, which installs CageFS. The Isolation Report shows whether CageFS is installed.

Known limitations ​

  • Converting to CloudLinux is effectively irreversible and requires a reboot to take effect. Take a provider snapshot before you start.
  • MySQL Governor is installed by CloudLinux but is not managed from the AdminBolt panel. AdminBolt does not provide MySQL Governor configuration or per-database limits.
  • Deep LVE tuning lives in the embedded LVE Manager UI, not in native AdminBolt panel screens. CageFS can be switched per account on the hosting account form.

Further reading ​

The LVE Manager, language selectors, CageFS, and MySQL Governor are CloudLinux's own components. For in-depth reference on those features, see the CloudLinux documentation.