This comprehensive guide will walk you through the process of installing LiteSpeed on Plesk, including the setup of the LiteSpeed Plesk Extension on a Plesk server. Our instructions assume you are operating with a fully functional Apache-Plesk configuration. While there are various approaches to installing the LiteSpeed web server and its Plesk Extension, we will begin by focusing on the extension, then proceed to cover the installation of the LiteSpeed web server in detail.

For your convenience, here's an overview of the topics covered in this guide:

1. Requirements Before Installation
2. Installing the LiteSpeed Plesk Extension
3. How to Install LiteSpeed Web Server
4. Installing LiteSpeed Web Server from the LiteSpeed Plesk Extension
5. Running Tests with a Port Offset
6. Switching to LiteSpeed
7. Switching Between LiteSpeed and Apache
8. LiteSpeed on Plesk: Configuration Process
9. CloudLinux PHP Selector Integration
10. LiteSpeed Cache Management
11. QUIC Protocol Configuration
12. HTTP/2 and HTTP/3 Through Apache Configuration
13. TLS Security Enhancements
14. Accessing the WebAdmin Console
15. Plesk Login Page Customization

Requirements Before Installation

Before commencing the installation process, ensure you meet the following prerequisites:

1. An operational Apache server on your Plesk environment.
2. If present, your NGINX reverse proxy should be stopped. Further instructions on this are provided below.
3. Your PHP handler must be set to FastCGI. This setting allows the LiteSpeed web server to correctly follow the handler configurations.

How to Properly Stop the NGINX Reverse Proxy

In recent Plesk versions, NGINX might be configured as a reverse proxy server, positioned between Apache and the internet. It is crucial to stop the NGINX reverse proxy before proceeding with the LiteSpeed web server installation. This ensures that Apache operates as the sole web server responsible for handling live web traffic.

Failure to stop NGINX will prevent the LiteSpeed process from starting as required. If the NGINX reverse proxy is still running, you will encounter the following notification when attempting to access the LiteSpeed extension:

“LiteSpeed is not running. Apache is running (PID = 23136)

“NGINX reverse proxy server is currently running and must be stopped. Please go to ‘Server Management > Tools & Settings > Services Management’ and stop NGINX.”

To stop the reverse proxy, navigate through the Plesk Admin Console: Server Management > Tools and Settings > Server Management > Services Management > Reverse Proxy Server (NGINX), and then click the Stop button.

Once NGINX has been stopped, verify that Apache is configured to listen on ports 80/443. You can do this by executing one of the following commands:

netstat -lnp | grep httpd

or

netstat -lnp | grep apache

If Apache is not configured correctly, you will need to run the command plesk repair web to rebuild the Apache configuration file.

Installing the LiteSpeed Plesk Extension

Follow these detailed steps to install the LiteSpeed Plesk Extension:

1. Download the most recent Plesk extension package directly from the LiteSpeed website.
2. Edit the file located at /usr/local/psa/admin/conf/panel.ini. If this file does not exist, create it.
3. Add the following content to the file before saving:

   [ext-catalog]
   extensionUpload = true

4. Within Plesk, navigate to Extensions > My Extensions. Click the Upload Extension button and then upload the package you downloaded in the first step.

How to Install LiteSpeed Web Server

There are two primary methods for installing the LiteSpeed Web Server on Plesk: either through a script or directly via the LiteSpeed Plesk Extension. It's important to note that the script method will only install the LiteSpeed Web Server and will not automatically install the Plesk extension itself.

Installing LiteSpeed Web Server Via Script

This script-based method is generally recommended, especially if this is your first time installing LiteSpeed. We will thoroughly explain all the options presented during the installation phase to help you complete it as efficiently as possible.

The installation of LiteSpeed is straightforward. Begin by signing into your server via SSH.

Next, execute the following command, replacing your_serial_nr with your actual LiteSpeed License Key:

bash <( curl https://get.litespeed.sh ) your_serial_nr

This intelligent script will automatically detect your environment, ensuring that only the necessary dependencies and installation data are downloaded from the LiteSpeed servers. Depending on the detected environment, the script will prompt you to answer several questions before initiating the LiteSpeed Web Server installation.

Helpful Hint: If you wish to utilize a trial license with the script, you should replace your_serial_nr with the word TRIAL (written exactly as shown, in all capital letters) in the command:

bash <( curl https://get.litespeed.sh ) TRIAL

Using TRIAL will automatically request a trial license for your server before LiteSpeed Web Server is installed. Should you encounter any errors when using a trial license, please refer to the helpful FAQ section.

Once the script starts, it will recognize that the installation is on Plesk and will present you with the following prompts for your input:

• Could not find an lsws.options file

  Could not find an lsws.options file. We will ask you for your preferred settings instead, but for automated bulk provisioning, you may want to exit and create an lsws.options file. Continue Installer(Y/N) ?

  This prompt is normal for a detailed, manual installation. The lsws.options file is primarily used for fast, automated installations. Press Y and then Enter to proceed.

• Enable PHP_SUEXEC

  Enable PHP_SUEXEC. Run PHP processes as the account owner. Available values: 0 (off), 1 (on), and 2 (user home directory only).

  This option determines how your server executes PHP processes. For shared hosting environments, a value of 2 (user home directory only) is highly recommended and is often the default setting.

• Apache port offset

  Apache port offset. Run LiteSpeed in parallel with Apache. For example, if set to 1000, Apache will listen on port 80, and LiteSpeed on 1080. If set to 0, Apache and LiteSpeed will use the same port, and LiteSpeed will not automatically start after installation.

  This critical option defines the port to which the LiteSpeed Web Server will bind upon installation. It is strongly advised to set the port offset to a value other than 0 (such as the default value of 1000). This allows LiteSpeed and Apache to run simultaneously, enabling you to thoroughly test LiteSpeed's functionality on your server before making it the primary web server.

  You can adjust the port offset to 0 once the installation is complete and you are confident that your websites function correctly with LiteSpeed. If you choose to set the port offset to 0 initially, LiteSpeed will start immediately after installation, and Apache will be stopped. In this scenario, you will also need to enable the "Switch to LiteSpeed Automatically" option, which will be covered further below.

• Admin username

  Admin username. For accessing LiteSpeed WebAdmin console.

  This option specifies the username you will use to log into the LiteSpeed WebAdmin Console. This console is essential for monitoring LiteSpeed statistics and controlling its behavior after installation. It is highly recommended to configure a secure username. The default value is admin.

• Admin email address

  Admin email address. Receive important server notices, such as license expiration and server core dumps.

  This option sets the email address where you will receive warnings, errors, and important notices from the LiteSpeed Web Server. To avoid missing crucial updates, it is advisable to choose an email address that you monitor regularly. The default value is root@localhost.

• Switching PHP Handlers

  Automatically switch PHP handlers for users and/or subscriptions inside of Plesk. Available values: 0 (No change), 1 (Switch just for users), 2 (Switch just for subscriptions), 3 (Switch for both users and subscriptions).

  This option asks whether you intend to automatically switch PHP handlers for users and/or subscriptions within Plesk. The default value is 0 (No change).

• Switching to LiteSpeed Web Server

  Switch to LiteSpeed Web Server. Automatically switches at the end of the installation if the port offset is set to 0. Available values are 1 (enable) and 0 (disable).

  This option determines whether the installer should automatically shut down Apache and switch to LiteSpeed Web Server immediately after its installation. If you previously configured the Apache Port Offset to 0, you should set this option to 1. The default value is 0.

Quick/Automated Installation

For scenarios requiring rapid deployment or bulk provisioning of LiteSpeed on Plesk, an automated installation method is available. This approach leverages shortcuts to streamline the setup process.

While running the installer script manually is sufficient in most cases, you can automate the process for bulk provisioning by creating an lsws.options file. This file should be placed in the directory from which you run the script command (e.g., /root/) or uploaded to your organization's internal repository. This allows the installer to retrieve all installation options directly from the file, eliminating the need for manual user input.

A typical lsws.options file will resemble the following structure:

php_suexec="2"
port_offset="1000"
admin_user="admin"
admin_pass="a1234567"
admin_email="root@localhost"
auto_switch_php="1"
auto_switch_to_lsws="0"

Note the addition of admin_pass in this configuration. This new option defines the password you will use to access your LiteSpeed WebAdmin Console. Ensure you set a strong, secure password for internal use only.

To implement this automated process, create your lsws.options file and store it on your local network for bulk provisioning. For example, at a URL like yourlink.com/yourinternalrepo/lsws.options. Then, execute the following command:

curl -o lsws.options yourlink.com/yourinternalrepo/lsws.options && bash <( curl https://get.litespeed.sh ) your_serial_no

Important notes:

• yourlink.com/yourinternalrepo/lsws.options should be replaced with the actual link to your personalized lsws.options file, which your servers must be able to access.
• lsws.options indicates the location of the lsws.options file. It is acceptable to leave it as is if the installer is run from the same directory where the lsws.options file resides.
• your_serial_no represents your LiteSpeed Web Server license key. As with the manual installation, you can use TRIAL if you wish to request a trial license. If you encounter an error when utilizing a trial license, please consult the FAQ.

Installing LiteSpeed Web Server from the LiteSpeed Plesk Extension

The LiteSpeed Plesk Extension provides a user-friendly graphical interface for installing the LiteSpeed Web Server. Access the extension by navigating to Server Management > Extensions > LiteSpeed Extension in your Plesk panel.

Once in the extension interface, click on Install LiteSpeed Web Server.

You will be presented with the comprehensive License Agreement. After reviewing it, tick the I agree box. You will then need to enter your license's serial number or opt to request a trial license if you do not have one yet.

Scroll down the page to find the Installation Options and WebAdmin Console Login sections.

For the Installation Options, the default values are generally suitable, but it is highly recommended to set a non-zero Port Offset (e.g., 1000) during your initial installation. For shared hosting environments, Enable PHP SuEXEC is recommended and is enabled by default. In the WebAdmin Console Login section, you primarily need to input a secure password, although utilizing a unique username different from the default "admin" is advised for enhanced security.

Once you have configured these settings to your satisfaction, click the Install button located below the WebAdmin Console Login section.

A confirmation message will appear, stating that LiteSpeed has been "installed successfully." This message will include details such as the platform detected, the latest stable version installed, and the download directory created.

At the bottom of the page, click Okay and then initiate the LiteSpeed Web Server by clicking the Restart LiteSpeed button.

If the process completes successfully, your LiteSpeed Extension page will display a message confirming that LiteSpeed and Apache are operating on separate ports. Typically, Apache will run on the standard port 80, and LiteSpeed on port 1080 (assuming you set your port offset to 1000).

For staging servers or test environments, you might not need to test LiteSpeed on an offset port. Furthermore, certain applications (such as Magento or WordPress) may not function correctly when LiteSpeed is tested on an offset port. In such cases, you can directly "Switch to LiteSpeed" from the extension GUI or use the command line for testing as follows:

/usr/local/lsws/admin/misc/cp_switch_ws.sh lsws

Running Tests with a Port Offset

A significant advantage of using a port offset is the ability to run both LiteSpeed Web Server and Apache simultaneously. This parallel operation allows you to thoroughly test your hosted websites on LiteSpeed Web Server to ensure their complete functionality before you fully switch off Apache.

For example, if you have configured the port offset to 1000, your websites can be tested on port 1080 for HTTP requests and port 1443 for SSL requests. This provides a safe testing environment without disrupting your live Apache-served content.

Once you are fully satisfied that your websites perform as expected with LiteSpeed Web Server, you will be ready to transition LiteSpeed Web Server to be your primary server.

Switching to LiteSpeed

To make LiteSpeed Web Server your primary web server, listening on standard ports 80 and 443, navigate to the "Switch between Apache and LiteSpeed" section within the LiteSpeed Plesk Extension. Click on Switch to LiteSpeed. This action will gracefully stop Apache.

Upon successful completion, LiteSpeed will be actively running as your primary web server. You will receive a confirmation message indicating that "LiteSpeed is running" and "Apache is not running," along with an affirmation that you "Switched to LiteSpeed successfully."

Switching Between LiteSpeed and Apache

You can seamlessly switch between LiteSpeed and Apache using the intuitive LiteSpeed Extension GUI within Plesk. Alternatively, for command-line users, you can execute the switching script:

To switch to Apache:

/usr/local/lsws/admin/misc/cp_switch_ws.sh apache

To switch to LiteSpeed:

/usr/local/lsws/admin/misc/cp_switch_ws.sh lsws

This flexibility ensures you can easily manage your web server environment as needed.

LiteSpeed on Plesk: Configuration Process

This section outlines various configuration aspects to optimize LiteSpeed's performance within your Plesk environment.

PHP Configuration

LiteSpeed works harmoniously with Plesk PHP right out of the box. The only essential step required is to ensure your PHP handler is set to FastCGI. This prevents any potential issues arising from mismatched PHP settings.

By default, LiteSpeed will automatically respect Plesk’s PHP settings, eliminating the need for further configuration. However, if CloudLinux PHP Selector is enabled and you prefer to use it as your PHP manager, additional handlers will be necessary. This will be detailed in a later section of this guide.

Disabling PHP Override in .htaccess

LiteSpeed Web Server provides the capability to disable PHP overrides within the .htaccess file.

Traditionally, php_value and php_flag directives could be used in Apache configuration or .htaccess to override php.ini settings. However, these are primarily supported by Apache’s mod_php handler, which has been deprecated in most control panel systems, being replaced by php-fpm, LSPHP, or fastcgi.

Consequently, if you place php_value or php_flag in an .htaccess file, Apache would typically return an error. You can find more comprehensive details regarding this in Plesk’s official documentation.

You might encounter one of the following errors:

• 500 internal server error
• 503 Invalid command 'php_flag', perhaps misspelled or defined by a module not included in the server configuration.
• In the domain error log (accessible via Domains > example.com > Logs), you might see:

  /var/www/vhosts/example.com/httpdocs/.htaccess: Invalid command 'php_value', perhaps misspelled or defined by a module not included in the server configuration

  /var/www/vhosts/example.com/httpdocs/.htaccess: Invalid command 'php_flag', perhaps misspelled or defined by a module not included in the server configuration

  /var/www/vhosts/example.com/httpdocs/.htaccess: RewriteRule: bad flag delimiters

  /var/www/vhosts/example.com/public_html/.htaccess: Invalid command 'suPHP_ConfigPath', perhaps misspelled or defined by a module not included in the server configuration.

LiteSpeed Web Server, which utilizes LSPHP, natively supports the use of php_value and php_flag in .htaccess. Unlike Apache, LiteSpeed Web Server will not return a 500 error in these situations, as it has greater tolerance for these PHP overrides.

Nevertheless, in certain scenarios, you may choose to disable such PHP overrides in .htaccess for LiteSpeed as well. To achieve this, you can employ a dedicated Apache directive: DisablePhpOverride htaccess, which can be applied at the server level within httpd.conf.

For example, on Plesk, create a file named DisablePhpOverrideLiteSpeed.conf in the appropriate directory based on your operating system:

CentOS:

/etc/httpd/conf.d/

Debian/Ubuntu:

The DisablePhpOverrideLiteSpeed.conf file should contain the following line:

DisablePhpOverride htaccess

Customized PHP Configuration

As of LiteSpeed Web Server v5.3, PHP is automatically detected, eliminating the need for manual PHP external application configuration. Plesk is the preferred PHP manager in most cases.

However, if you require a customized configuration for a specific PHP version, you might need to manually create and configure the external application. From the LiteSpeed Web Server Admin Console, you can create lsphpXX instances (e.g., lsphp70, lsphp71, lsphp72) one at a time.

Simply adjust the Name, Address, and Command settings to correspond with the relevant PHP version. If you prefer using the command line over the GUI, you can edit the LiteSpeed Web Server configuration file, typically found at /usr/local/lsws/conf/httpd_config.xml.

CloudLinux PHP Selector Integration

When CloudLinux PHP Selector is enabled alongside Plesk PHP settings, it can be unclear which PHP Selector is actively in use. While LiteSpeed automatically respects Plesk’s PHP selection by default without additional configuration, you will need to make a few adjustments if you wish to utilize the CloudLinux PHP Selector.

To bring the CloudLinux PHP Selector into effect, you need to:

• Set up an extra handler for LiteSpeed, which will redirect Plesk PHP to CloudLinux for non alt-phpxx versions.
• Select a non alt-php version within Plesk’s PHP settings.

These actions combined will ensure that the CloudLinux PHP Selector is utilized.

Configure an Extra Handler for CloudLinux PHP

Access the LSWS Web Admin Console and navigate to Server > PHP > Add PHP Handlers. Configure the settings as follows:

• Handler ID: php
• Command: /var/www/cgi-bin/cgi_wrapper/cloudlinux_wrapper
• Handled Suffixes: php, php54, php55, php56, php70, php71, php72, php73, php74

These settings will ensure that the listed Plesk PHP versions are directed to utilize the CloudLinux PHP selector.

Alternatively, if you prefer command-line configuration, you can directly edit LiteSpeed’s configuration file:

vi /usr/local/lsws/conf/httpd_config.xml

Insert the following within the <phpConfig>...</phpConfig> tags:

<handler>
    <suffix>php, php54, php55, php56, php70, php71, php72, php73, php74</suffix>
    <type>lsapi</type>
    <command>/var/www/cgi-bin/cgi_wrapper/cloudlinux_wrapper</command>
</handler>

Select Plesk PHP for CloudLinux Integration

After successfully creating the handler, proceed to Plesk’s PHP settings. From the PHP support dropdown, select any PHP version that is not one of the alt-php versions (i.e., choose one of the versions listed in the PHP handler you just created). This selection is crucial to ensure that the CloudLinux PHP selector is effectively utilized for your domains.

LiteSpeed Cache Management for WordPress

The LiteSpeed Plesk Extension simplifies the mass installation of the LiteSpeed Cache (LSCache) plugin across all WordPress installations on your server. After installing the LiteSpeed Plesk Extension, you might initially encounter a "No Cache Management data file found" message.

Setting the Cache Root

To resolve the "No Cache Management data file found" message, click on Manage Cache Installations. Within the Cache Root Setup section, click Set Missing Cache Roots. This action will configure the necessary cache directories for your WordPress installations.

Scanning and Enabling LSCache for WordPress

Once the cache root has been successfully established, return to the main LiteSpeed Extension page. Click the Manage Cache Installations option once more.

The next step involves scanning for all WordPress installations across your server and subsequently installing the LiteSpeed Cache Plugin for WordPress (LSCWP) on them. First, you will need to select the desired LSCache plugin version for installation. It is generally recommended to choose the latest stable version available.

This process is designed to be user-friendly. While the initial scan may take some time, depending on the number of sites hosted on your server, subsequent scans can be expedited by using the Discover New button, which only searches for sites not yet discovered.

Once the scan is complete, you will gain the ability to manage the discovered WordPress sites. You can activate the LiteSpeed Cache Plugin for WordPress either individually for specific sites or perform a bulk activation for multiple websites simultaneously. A green light symbol in the Cache Status column will indicate successful LSCWP activation.

To verify that a site is correctly cached, examine the x-litespeed-cache:hit response header. Its presence signifies that caching is functioning as intended.

QUIC Protocol Configuration

The QUIC protocol utilizes UDP port 443 for its connections. It is imperative to ensure that this port is not being blocked by your server's firewall to allow QUIC to function correctly and enhance connection speed and security.

HTTP/2 and HTTP/3 Through Apache Configuration

You have the flexibility to enable or disable various protocols, including HTTP/2 and HTTP/3, directly within your httpd.conf file using the SpdyEnabled directive. The syntax is as follows:

SpdyEnabled http3

Valid alternative parameters for this directive include:

• spdy2
• spdy3
• http2
• off

By default, all protocols are enabled. Therefore, if you wish to utilize all SPDY, HTTP/2, and HTTP/3 protocols, there is no need to include a SpdyEnabled directive.

Helpful Hint: When employing this directive to explicitly enable specific protocols, any protocols not explicitly selected will be automatically disabled. For instance, `SpdyEnabled http2` will enable HTTP/2 while simultaneously disabling SPDY and HTTP/3. Exercise caution to avoid inadvertently disabling protocols that you require for your web services.

TLS Security Enhancements

To bolster the security features of your Plesk environment, it is highly recommended to enable TLS 1.3 and disable any weak cipher suites. By default, Plesk configurations enable TLS 1.0, TLS 1.1, and TLS 1.2. This guide will demonstrate how to enable the more secure TLS 1.3 protocol.

These instructions have been created and tested on Plesk 17.8 and CentOS 7.5. For Debian/Ubuntu Plesk installations, the relevant configuration files will typically be found in /etc/apache2/mods-available/ssl.conf.

Important Reminder: As with any modifications to Apache configuration files, it is essential to restart the server after making the adjustments detailed below. Use the following command for restarts:

systemctl restart lsws

Enabling TLS 1.3

To enable TLS 1.3, you need to edit the file /etc/httpd/conf.d/ssl.conf.

Locate and comment out (by adding a # at the beginning of the line) the existing SSL protocol and cipher suite directives:

#SSLProtocol +TLSv1 +TLSv1.1 +TLSv1.2
#SSLCipherSuite HIGH:!aNULL:!MD5

Then, replace these lines with the following to enable TLS 1.1, TLS 1.2, and TLS 1.3:

SSLProtocol TLSv1.1 TLSv1.2 TLSv1.3
SSLCipherSuite HIGH:!aNULL:!MD5

If you wish to further enhance security by disabling TLS 1.1 as well, modify the SSLProtocol line to:

SSLProtocol TLSv1.2 TLSv1.3

Disabling Weak Cipher Suites (Optional)

Plesk typically includes several weak cipher suites by default. For enhanced security, you can disable them. The default cipher suite line might look like this:

SSLCipherSuite HIGH:!aNULL:!MD5

Replace it with the following more robust cipher suite configuration:

SSLCipherSuite TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA256:TLS_AES_256_GCM_SHA384:TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256:TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384:TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256:TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA:TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384:TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA

Please be aware that employing a more restrictive set of cipher suites might potentially lead to an increased CPU load. It is recommended to test your configuration thoroughly, for example, using tools like SSL Labs, to ensure optimal performance and security balance.

Accessing the WebAdmin Console

The LiteSpeed WebAdmin Console for Plesk utilizes port 7088, distinguishing it from the standard port 7080. It is crucial to verify that port 7088 is enabled in your server's firewall. Once confirmed, you should be able to access the WebAdmin Console securely via https://SERVER_IP:7088.

Plesk Login Page Customization

You can configure your Plesk login page to be accessible without needing to specify a URL port number. For instance, a URL like https://IP-or-domain:8430 can be simplified to https://domain.com.

To achieve this, create a virtual host (vhost) in Plesk and then add the following rewrite rule to its .htaccess file:

RewriteRule ^(.*)$ https://127.0.0.1:8443/$1 [P,L]

This rule redirects requests for your domain to the Plesk login page without the explicit port in the URL, providing a cleaner and more professional access point.

We hope this comprehensive guide has provided you with all the necessary information to successfully install, configure, and optimize LiteSpeed Web Server on your Plesk environment. By following these steps, you can enhance your server's performance, security, and overall efficiency, ensuring a robust hosting solution for your websites.