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Suppressing Non-Critical Banners

Sometimes the LiteSpeed Cache plugin for WordPress adds informational banners to your WordPress Dashboard, such as this one:

These banners are meant to be informational, but they are not critical to the functioning of the plugin. As of LSCWP v3.0, these banners are opt-in only, meaning by default, such non-critical banners will not be displayed. If you would like to opt in to seeing LiteSpeed news (hotfixes, new releases, available beta versions, promotions, etc.) displayed on your dashboard, navigate to LiteSpeed Cache > General > General Settings and set Notifications to ON.


This setting does not suppress notifications such as Purged all caches successfully. and other messages related to the functioning of the plugin.

Admin IP Commands

LSCWP's admin IP commands give you access to certain actions from the browser window by way of a simple query string.

To trigger one of these actions for a page, access the page with the ?LSCWP_CTRL=ACTION query string appended to the end of the URL.


To purge the blog post, you would visit this URL:

The PURGE action, and most others, are restricted by IP address. You can give trusted users and admins access to all of the actions by adding their IP addresses in Toolbox > Debug Settings > Admin IPs. You do not need to be logged in to use these actions.

Used for Admin IP required
NOCACHE Display a page without caching it. An example use case is to compare a cached version of a page with an uncached version. Yes
before_optm View the page without any of the optimizations enabled. No
SHOWHEADERS Display all of the cache headers associated with a page in the Inspect tool. Yes
PURGE Purge all cache tags associated with the page, except the blog ID tag. Pages with the same cache tag will be purged as well. Yes
PURGESINGLE Purge only the first cache tag associated with the page. Yes


Actions are case-sensitive.

WordPress CLI

This documentation has moved to it's own page. Please see WordPress CLI.

Using a Default Configuration

The const.default.ini file contains the default configuration for LSCWP. It can be used, for example by hosting providers, to change the default settings for the plugin. The file is located in the /wp-content/litespeed-cache/data folder.

As of v3.3 of our WHM plugin, hosting providers can use a custom const.default.ini file when enabling or mass enabling LSCWP by placing the file under the /usr/src/litespeed-wp-plugin directory. This file will then be used for all sites installing a new copy of LSCWP.

Changes to const.default.ini do not prevent users from changing their plugin settings.

Using Multiple Optimization Plugins

LiteSpeed Cache for WordPress has many optimization features in addition to our signature full-page cache, and as such, you probably don't need any other similar plugins. If you still want to use one of the other WordPress optimization plugins for whatever reason, that shouldn't be a problem, as long as you don't try to use the same features in both.

For example, if you are using our full-page cache and our CDN support, then you will need to make sure that page cache and CDN support are disabled in whatever other plugin you use. Similarly, if you are using a minification function (for example) in another plugin, you will need to keep minification disabled in our plugin.

Duplicating functionality at best bogs down your server, and at worst breaks your site. So don't do it!

To learn more about this, see our blog.

Compatibility Check

Not all cache plugins are good candidates to pair with LiteSpeed. In order to avoid duplicating our functions, a plugin must either:

  1. not include the same cache and optimization functions as LiteSpeed Cache at all, or
  2. include cache and optimization functions that can be disabled one-by-one.

Set up Other Plugin

Before you install and activate LiteSpeed Cache, you should first get the other plugin working to your satisfaction. Doing this part first will make it easier because you can follow the plugin’s given directions without having to worry about how it will impact LiteSpeed’s setup.

Once the plugin is installed, activated, and set up to your liking, purge that plugin’s cache to ensure there are no conflicts from the start, and then disable the cache and all of the duplicate optimization functions that you plan to use in LSCWP.

Set up LSCWP

Install and activate LSCWP. Enable the cache and any optimization features you wish to use in LSCWP.


At this point, you should have both plugins working together in harmony, but you’ll want to do a quick test, just to be sure. To verify that your pages are actually being cached by LiteSpeed, you can follow these steps.

If the page was not cached by LiteSpeed, then something in your setup is not quite right. Contact us, if you need help!

If the page was cached by LiteSpeed, then the setup is finished. Don’t forget to take a look at your LiteSpeed Cache settings and see if anything needs adjustment. In general, the default settings are fine, but you might want to tweak a few things since you’ve got the other plugin running, too.

Translate LSCache for WordPress

LSCWP is written in United States English, and so we rely our our international users to help us translate the plugin for worldwide use. If you are fluent in a language other than English (US), and you have a few minutes to contribute to our plugin, we would appreciate it!

Is Your Language Needed?

We have a few languages very well covered, so you'll want to check the Translating WordPress page for LiteSpeed Cache and look for your language (and geographic location if applicable). If there are red or yellow boxes next to the language, then your expertise is needed.

As you can see, we have quite a few red boxes as of this writing (and several pages more of them past where the screenshot ends). The most important column is the "Stable" column. Languages with shades of red in the stable column have less than a third of the plugin translated.

Submit a Translation

All you need is a login. Once you are logged in, you can click the link and start translating at your own pace.

The instructions will be the same for whichever language and geographic location you choose, but for simplicity's sake, let's say you're from Spain and would like to contribute to the Spain Spanish translation.

Click Spanish (Spain) to be brought to the es_ES translation page.

The most important section to work on first is Stable (latest release), so click on that to see what strings are still missing translation.

You'll be brought to a list of strings and their current translations (if any).

This list, if it's not well-populated, may look overwhelming. However, it is not required for you to translate every single string. You could spend half an hour and do thirty of them. Or ten. Or even just one. Every contribution, even a small one, gets us closer to full translation.

When you see a string you'd like to translate (for example, Communicated with Cloudflare successfully), double click on the Translation column for that string, and enter your translation in the box.

Click the Suggest new translation -> button. Congratulations, you have successfully translated your first string.


All translations must be approved by an editor for your language before they are incorporated into the plugin.

If you would like to be a translation editor for LSCache, just keep translating! We will notice you, and apply to to give you editor access. Additionally, we'll add you to our Slack team, where you can communicate with our other editors, and be kept in the loop for new plugin updates and needed translations.

Thank you for helping us make LSCWP accessible for a global audience!

Enabling and Limiting the Crawler

These instructions apply to the WordPress LSCache crawler and other CMS LSCache crawlers where available.

Due to the potential of the crawler to consume considerable resources, we have put the on/off switch in the hands of the server administrators. In a control panel environment, such as cPanel, the crawler is disabled by default and can only be enabled by an admin through Apache configuration. In the LSWS Native environment, the crawler is enabled by default and can be disabled at the server level or virtual host level in LSWS v5.3.5 and above.


We do not recommend enabling the crawler for shared hosting setups unless the server has enough capacity to handle it!

Shared Hosting / Control Panel Environment

As of LSWS v5.1.16, there are four different approaches you can take to crawling on your server:

  • You can disable it for the entire server
  • You can disable it for the entire server, and selectively enable it for specific vHosts
  • You can enable it for the entire server
  • You can enable it for the entire server, and selectively disable it for specific vHosts

Enabling the Crawler

To enable the crawler in either of the second two scenarios, you need to add this “Crawler Snippet” to the appropriate configuration or include file:

    <IfModule Litespeed>
     CacheEngine on crawler

The exact location of the relevant configuration or include file varies, depending on the control panel you use (or if you use no control panel at all), and which of the above options you are looking to enact. See below for instructions relevant to your setup.


This snippet should not be added to .htaccess. It must be added to an Apache configuration file.

After you've added the Crawler Snippet in the appropriate location, you should gracefully restart the server.

Limiting the Crawler

Currently, the following variables are available for use with the Crawler function:

  • CRAWLER_USLEEP puts a minimum allowed value on the Delay field.
  • CRAWLER_LOAD_LIMIT sets a default for the Server Load Limit field.
  • CRAWLER_LOAD_LIMIT_ENFORCE sets a maximum allowed value on the Server Load Limit field.

To use these variables, add them one-per-line to the appropriate configuration file. For example:

    <IfModule LiteSpeed>
    CacheEngine on crawler
    SetEnv CRAWLER_USLEEP 1000

Disabling the Crawler

You may disable the crawler for an Apache virtual host, in any situation. Simply add CacheEngine -crawler to the Apache virtual host configuration, like so:

    <IfModule LiteSpeed>
    CacheEngine -crawler


Server Level

Change your working directory to:

  • /usr/local/apache/conf/includes/ for EA3 or
  • /etc/apache2/conf.d/includes/ for EA4.

Add the Crawler Snippet and optional server variables to the pre_main_global.conf file.

Global Virtual Host Level

Change your working directory to:

  • /usr/local/apache/conf/userdata/for EA3 or
  • /etc/apache2/conf.d/userdata/ for EA4

If these directories do not exist, create them.

Add the Crawler Snippet and optional server variables to the lscache_vhosts.conf file.

Apply these changes to all Virtual Hosts by running the following command:

    /scripts/ensure_vhost_includes --all-users


You only need to run this command once and it will activate for all users, including new users created by WHM later. There is no need to edit the cPanel skeleton file.

Individual Virtual Host Level

Change your working directory to:

  • For EA3: /usr/local/apache/conf/userdata/std/2_4/<user>/<domain>/
  • For EA4: /etc/apache2/conf.d/userdata/std/2_4/<user>/<domain>/

If your site supports HTTPS (SSL), please also change that working directory to:

  • For EA3: /usr/local/apache/conf/userdata/ssl/2_4/<user>/<domain>/
  • For EA4: /etc/apache2/conf.d/userdata/ssl/2_4/<user>/<domain>/


The 2_4 in the path is an example. You can replace it with your appropriate version, such as 2 or 2_2.

If these directories do not exist, create them.

Add the Crawler Snippet and optional server variables to the lscache_vhosts.conf file. This will enable the crawler for this Virtual Host only.

Apply these changes by running the following command:

    /scripts/ensure_vhost_includes --user=$user


Server Level

Change your working directory to:

  • /etc/httpd/conf.d/ for CentOS
  • /etc/apache2/conf.d/ for Debian
  • /etc/apache2/conf-enabled for Ubuntu

Add the Crawler Snippet and optional server variables to lscache.conf. If it doesn’t exist, create it.

Global Virtual Host Level

Change your working directory to /usr/local/psa/admin/conf/templates/custom/domain

Create it if it doesn’t exist.

Copy /usr/local/psa/admin/conf/templates/default/domain/domainVirtualHost.php to this location.

Edit the file and add the Crawler Snippet and optional server variables after the mod_suexec.c block.

Reconfigure all virtual hosts (this will regenerate new configuration files for all vhosts), like so::

    /usr/local/psa/admin/bin/httpdmng --reconfigure-all
Individual Virtual Host Level

Change your working directory to /var/www/vhosts/system/<domain_name>/conf/

Create a file called vhost.conf if it does not already exist ( or vhost_ssl.conf for HTTPS sites).

Add the Crawler Snippet and optional server variables to this file.

Reconfigure this Virtual Host (this will regenerate new configuration files for this vhost), like so:

    /usr/local/psa/admin/bin/httpdmng --reconfigure-domain <domain_name>


Server Level

Add the Crawler Snippet and optional server variables to the /etc/httpd/conf/extra/httpd-includes.conf file.

Global virtual host level

Create a /usr/local/directadmin/data/templates/custom/cust_httpd.CUSTOM.2.pre file and add the Crawler Snippet and optional server variables to it.

Apply these changes to all Virtual Hosts by running the following commands:

    cd /usr/local/directadmin/custombuild
    ./build rewrite_confs

LiteSpeed Native

The cache crawler is enabled by default in a LSWS Native environment.

To disable it at the Server Level, you will need to use LSWS 5.4 and above. There was a Cache Features function added to control this.

In the LSWS WebAdmin interface, navigate to LSWS Admin > Configuration > Server > Cache. In Cache Features, check On, uncheck Crawler, check ESI, and uncheck Not Set.

If Not Set is checked, the other three values will be ignored and the default values will be used. (By default, all three are checked.)

To disable the cache crawler at the LSWS Native Virtual Host level, navigate to LSWS Admin > Configuration > Virtual Host > VH Name > Cache >, and set Cache Features in the same manner as above. If Not Set is checked, the other three values will be ignored and the server-level configuration will be inherited.


Do not set Enable LiteMage to On, as this setting will also enable the crawler, even if Crawler is unchecked.

To add any of the optional server variables, navigate to Server > External App and add the variable(s) to the Environment setting, one per line. For example:


Verifying Crawler Status

To determine whether the crawler is enabled or disabled, you can check the phpinfo page and look at the value of the X-LSCACHE server variable. If the variable contains crawler, then the crawler is enabled at the server level. If it does not contain crawler, as in the example and screenshot below, then you know the crawler is disabled at the server level.

    $_SERVER['X-LSCACHE'] on,esi


The X-LSCACHE server variable only controls LiteSpeed's own crawler. Third party crawlers are not beholden to the value of X-LSCACHE and cannot be controlled that way.

Additionally, you can check the status of the crawler in the LiteSpeed cache for WordPress plugin. Navigate to Crawler > Summary. If Crawler Cron is set to Disable, and you see the following warning, then the crawler is disabled at the server level:

    Warning: The crawler feature is not enabled on the LiteSpeed server. Please consult your server admin.

Changing your cache storage location

If you would like to change the location where LiteSpeed stores your cached content, you can use the LITESPEED_DATA_FOLDER constant.


To set your cache storage directory to cache/litespeed, add the following line to your wp-config.php file:

define('LITESPEED_DATA_FOLDER', 'cache/litespeed');

Replacing WordPress Cron

The WordPress cron controls the publishing of scheduled posts and the running of LiteSpeed's optimization queues, among other things.

WP cron runs when PHP is triggered. However, in order to speed up your site, LiteSpeed Cache's goal is to minimize the usage of PHP. Avoiding PHP is great for performance, but it's not so good for timely executing scheduled tasks.

We recommend that you take control of the WP cron system away from PHP and give to your system cron instead.

Here's how to set that up in cPanel:

Disable WP cron

Add the following to your site's wp-config.php:

define('DISABLE_WP_CRON', true);

This tells WordPress not to automatically run its cron when PHP is triggered.

Add a new job to system cron

In cPanel, navigate to Tools > Advanced > Cron jobs.

Under Common Settings, choose one of the predefined intervals. We like Once Per Five Minutes(*/5 * * * *), but you can run it as frequently or as infrequently as you wish.

Set Command to the following:

wget -q -O - >/dev/null 2>&1

Press the Add New Cron job button.

You've now set wp-cron to run on a reliable every-five-minutes schedule for the domain.


There are a number of ways to execute wp-cron, but in order to avoid negating the benefits of our caching system, we recommend you use wget instead of the WP CLI or PHP CLI.


In some cases, a strict security system may block a WP cron request. To test whether this is happening on, run this command, and replace USERNAME with your cPanel username:

wget -O /dev/null >> /home/USERNAME/cron.log 2>&1

Check the /home/USERNAME/cron.log file and make sure the HTTP response header is returning 200 OK.

Setting Up CloudFront CDN

Create CDN with CloudFront

  1. Set up AWS CloudFront CDN
  2. Get your CloudFront Domain Name
  3. Make sure your site can be visited directly through the CloudFront Domain Name

Set Up in LSCache Plugin

  1. From the WP Dashboard, navigate to LiteSpeed Cache > CDN > CDN Settings.
  2. Set Use CDN Mapping to ON
  3. Enter CDN URL as your CloudFront Domain Name
  4. Enable the relevant Include buttons. e.g. Images and CSS. For this example, since we don't Include JS, then we also need to remove .js from Include File Types
  5. Set up Original URL as your original domain name (and sub-folder if you are using one)


Check that the CSS is served from CloudFront

Check that the JS is served from the original domain

Turning WordPress Shortcodes into ESI Blocks

You can turn WordPress shortcodes into ESI blocks with LiteSpeed Cache. This allows you to cache the contents of the shortcode in a different way than you've cached the rest of the page. (You can learn more about ESI on our blog, if this concept is new to you.)

If you have a mycalendar shortcode, for example, and it inserts a calendar into your page, you might use it like this:

    [mycalendar month="November" year="2018"]
To turn it into an ESI block, you would instead use it like this:
    [esi mycalendar month="November" year="2018"]
By default, shortcode contents are stored in public cache, and the TTL defaults to whatever value you have stored in LiteSpeed Cache > Cache > TTL > Default Public Cache TTL, but you can change that with a few parameters. To store the shortcode contents in private cache for five minutes (or 300 seconds), you can say this:

    [esi mycalendar month="November" year="2018" cache="private" ttl="300"]


While LiteSpeed Cache can easily cache your shortcode contents, it is not possible for LSCache to purge the shortcode contents on demand. Shortcode ESI blocks can naturally expire when the TTL is reached, but a purge cannot be triggered by particular events. This makes sense, because LiteSpeed can't know which occurences should trigger a purge. Different shortcodes all have different events that render them out-of-date, and there's no way for LiteSpeed to know what they are.

Using the example of the calendar plugin above, let's say you use the following shortcode:

    [esi mycalendar month="November" year="2018"]
This will cache the mycalendar block for the same length of time as your site's default TTL. If someone edits an event before the TTL is reached, then the ESI block will, unfortunately, be out-of-date.

There are two ways to handle this issue:

  • Have the shortcode's plugin author use our API to trigger a purge when block content changes.
  • Use a short TTL, and live with the possiblity that contents may be out-of-date for a short time.

Get the Plugin Author Involved

If it's important that the shortcode contents be purged by specific events, you can share this API call with the author of the shortcode's plugin (just be sure to replace mycalendar with the actual name of the shortcode you want to purge:

do_action( 'litespeed_purge', 'esi.mycalendar' ) ;

This is the most precise way to keep the content in the shortcode up-to-date and accurately cached according to the shortcode's own requirements.

Do it Yourself

If it is not critical for the contents of the shortcode to have up-to-the-minute accuracy, then you can use the ttl parameter to cache the content for a short time. If you can live with content that is an hour old, set ttl="3600". If you are thinking more along the lines of five minutes, set it to ttl="300".

While it is possible to set the content to not be cached at all ( ttl="0"), it is not recommended. Any time there is uncached content on a page, PHP must be invoked in order to generate that content. PHP uses valuable resources, and significantly slows down a page. It's far better to cache your content for a small amount of time than to set it not to be cached at all.

Cookies and Cache

The relationship between cookies and caching can be easily misunderstood. When you talk about "caching cookies" or "not caching cookies," it's not the cookies themselves that are being cached or not cached. It's the pages of the site that are being cached or not cached based on whether a user has those cookies stored.

Cookies, generally, are ignored unless you specify otherwise. Cookies become important when they impact the user experience in some way.

Cookies Set or Read by WordPress

If a cookie must be set or read by WordPress, then it has to be excluded from cache. And, if the cookies are set on your site (i.e. they are not set somewhere before arriving at your site), then you will also have to exclude the page that sets the cookie's value.


Let's say your site is part of an affiliate network. When a user arrives at an aff-example cookie is set. As they navigate the site, the cookie is updated with tracking information.

In this case, the cookie aff-example must be added to the Do Not Cache Cookies list in LiteSpeed Cache > Cache > Excludes, and ^/afilliate_home must be added to Do Not Cache URIs list on the same page. (For more on the Excludes page, see the screen-by-screen documentation.)

If, in this example, the cookie was set at, but then never referenced again, you would not have to exclude the cookie from cache.

Alternately, if the cookie was set offsite somewhere, but was used for tracking as the visitor wandered around your site, then you would have to exclude the cookie from cache, but you wouldn't have to exclude the ^/afilliate_home URI.

Cookies That Indicate Variations

Sometimes cookies can be used to indicate important information about the user to WordPress, to help determine what content should be shown to the user. In these cases, you can use the cookies to create cache varies. When LSCache varies on a cookie, it caches separate public versions of the pages of the site, based on the value of the cookie.


Let's say your WP site is a shop, and you have special pricing for your friends that is activated when they visit That page sets a myfriend cookie, and from that point on, every page they visit in your shop shows pricing that is 20% less than normal. When a visitor without the myfriend cookie looks at the pages in your shop, they see regular prices.

Because the cookie is set on the page, that URI will need to be excluded from cache as described above.

There are two ways to deal with the cookie itself:

  • You could do as the previous example, and exclude it from cache. That's the easiest way, but it means your friends will always have uncached content, and that's not an ideal experience for them.
  • You could create a cache vary based on the myfriend cookie.


Assume you have a WooCommerce site with a "woocommerce_products_per_page" cookie. For some users, the value will be 10. For others it will be 100. And still others may have a value of 200. These three scenarios require three different views.

There are two ways to handle different views based on a cookie value:


The more efficient option is to find a JavaScript-based solution. A JavaScript plugin would only need to store one copy of the page and would build the display based on the existence of the cookie.

Rewrite Rules

If a rewrite rule-based answer is preferred, the site can be configured to vary on the cookie by adding the following rule to your site's .htaccess file:

<IfModule LiteSpeed>
CacheLookup on
RewriteRule .* - [E=Cache-Vary:woocommerce_products_per_page]

When a user visits your WooCommerce site, the woocommerce_products_per_page=xxxxxxcookie will be created. Using the rewrite rule above, the cache will vary on that cookie. This means the cache will store multiple copies: one for every value of the cookie that requests the page.


woocommerce_products_per_page is an example. Be sure to substitute the appropriate cookie name.

Further Reading

You can learn more about cookies and cache varies in our Developer's Guide to Cache Vary.

Memcached, LSMCD and Redis (Object Cache) Support in LSCWP

LiteSpeed Cache for WordPress supports Object Cache.

What is an Object Cache?

An object cache stores the results of expensive and/or frequent database queries in a way that makes them easy to retrieve, and eliminates the need for repeated access to the database. Object caching greatly reduces the time it takes to retrieve query results.

For example, your WordPress site's options are stored in the database. Site options include things like the site's name and URL. Every time a page is assembled for a visitor, it is necessary to access the database to read the site options. As you can imagine, these repeated queries for the same information represent wasted resources. With an object cache, you can query the database once, and save the results for a set period of time. During that time, whenever a page must be assembled, WordPress can get the site information from the cache. Accessing object cache is a much less resource-intensive prospect than accessing a database.

Some queries are time-consuming, and other queries are repeated frequently. Both of these scenarios can be improved by storing the query results in object cache.


If you have a site that is fully-cached by LSCWP, you won't use object cache very often. Object cache is only necessary when WordPress is building a page through PHP. If PHP is not being invoked (and minimizing PHP usage is the goal with LSCache) then there are no queries to process and therefore nothing to look up in object cache.

How to set up Object Cache Support

LSCWP doesn't provide object caching directly. Rather, it supports your use of an external object cache such as Memcached or LiteSpeed's drop-in Memcached replacement, LSMCD.

Install Memcached, LSCMD or Redis and PHP Extension

You will need a working and fully tested installation of Redis, Memcached, or LSMCD, as well as the related PHP extension (i.e. php-memcached or php-redis) in order to make your object cache work properly with WordPress.

See the following for additional instructions:

Config Object Cache in LSCWP

If you are using LSMCD, Memcached or Redis, you can set up LSCWP support in the Cache Settings tab. Navigate to LiteSpeed Cache > Cache > Object. You will need to give LSCWP some parameters, including where your Memcached or LSMCD lives, which objects you'd like to have cached, and how long you want objects to remain in cache, among other things.

Before enabling Object Cache, the default values will already be filled in for you.

After enabling Object Cache, the LSCache plugin will automatically run both connection testing and Memcached/Redis extension detection.

Detailed instructions for all of these settings can be found here.

Set a custom prefix (optional)

The LiteSpeed Cache plugin supports object cache prefixes, which prevent users on a server from reading the keys for other sites on the same server. By default we generate keys based on the md5 sum of the site's path, but you can define your own custom prefix for a site by setting the LSOC_PREFIX variable for that site.


To give a site an object cache prefix of ABC, add the following line to the site's wp-config.php file:

define('LSOC_PREFIX', 'ABC');

How to Verify

There are not too many methods to check the Object Cache log, but if you set LiteSpeed Cache > Toolbox > Debug Settings > Debug Log to ON or Admin IP, and view your page source code, you should see something like this at the bottom of the code:

    <!-- Object Cache [total] 5190 [hit_incall] 5056 [hit] 6 [miss_incall] 21 [miss] 107 [set] 171 -->

  • total is the total number of objects the page requested.
  • hit_incall is the number of objects that did not hit Memcached but hit the runtime data from above.
  • hit is the number of objects retrieved from Memcached.
  • miss_incall is the number of objects not set in runtime. That is to say, when php ran into the current line, no data was set before.
  • miss is the number of objects not found in Memcached.
  • set is the number of objects set in Memcached.

How to Debug

If your Connection Test shows Failed, there are a few things you can try.

  1. Try service memcached status, to make sure the service is active (running).
  2. Try ss -lptun | grep 11211, to make sure the Memcached port is listening.
  3. Try telnet localhost 11211, to make sure you can connect to localhost successfully.

Test files

You can create test PHP files to test connection

For Memcached:


    $conn = new Memcached ;
    $address = '/path/to/memcached.sock' ; // set the address here
    $port = 0 ; // set the port
    $conn->addServer( $address, $port ) ;
    var_dump( $address ) ;
    var_dump( $port ) ;
    var_dump( $conn->getStats() ) ;
    echo '<hr>';
For redis:

    $cfg_host = 'redis address' ;
    $cfg_port = '6379' ; // or 0 if use socket
    $cfg_pswd = '' ; // Set if has
    $cfg_db = 0 ;

    $conn = new Redis() ;
    $conn->connect( $cfg_host, $cfg_port ) ;
    if ( $cfg_pswd ) $conn->auth( $cfg_pswd ) ;
    if ( $cfg_db ) $conn->select( $cfg_db ) ;

    var_dump( $conn->ping() ) ; // Should give a `+PONG`

Integrate Redis with WordPress

Redis is an open source, in-memory data structure store, used as a database, cache and message broker. LSCache is the world's fastest full page caching. So it's useful for you to have both of them setup on your server. This guide can be used both with and without a control panel.

Install Redis daemon

CentOS 7

  1. Add the EPEL repository:
    yum install epel-release
  2. Install Redis:
    yum install redis
  3. Start Redis:
    systemctl start redis


  1. Install Redis:
    apt install redis
  2. Start Redis:
    systemctl start redis-server

Install Redis PHP extension

The phpredis extension provides an API for communicating with the Redis key-value store.

cPanel EasyApache 4 + CentOS

The following commands work for both CentOS 8 and 7:

/opt/cpanel/ea-php72/root/usr/bin/pecl install redis
echo '' > /opt/cpanel/ea-php72/root/etc/php.d/redis.ini

Or, navigate to WHM > Module Installer, choose PHP Pecl, select the appropriate PHP version, and install the extension from there.


Replace ea-php72 with whichever version of PHP you want to install the extension for.

If you'd like to install the extension for all available versions of PHP with a single block of code, see these instructions from BigScoots.

With Plesk

Generally, Plesk supports the php-redis extension. If your Plesk version does not support php-redis by default, please see the following instructions at Plesk.

With DirectAdmin

  1. DirectAdmin custombuild 2 will install phpxx to /usr/local/phpxx. You can go to the version you want (such as php73) to build php-redis through pecl:
    cd /usr/local/php73/bin
    ./pecl install igbinary igbinary-devel
    ./pecl install redis
  2. Check the path of extensions:
    ll /usr/local/php73/lib/php/extensions/
    drwxr-xr-x 2 root root 76 Mar  3 14:05 no-debug-non-zts-20180731
  3. Add both and to a newly created 10-directadmin.ini:
    vi /usr/local/php73/lib/php.conf.d/10-directadmin.ini
  4. Restart LSPHP to make the change effective:
    killall -9 lsphp

Without a Control Panel

  1. Add the LiteSpeed repository.

CentOS 7:

rpm -ivh

CentOS 8:

rpm -ivh
2. List the LiteSpeed Redis PHP extension:
yum list | awk '/lsphp/&&/redis/'
3. Install PHP (substitute your LSPHP version if it is different):
yum -y install lsphp71-pecl-redis

Verify the Installation

  1. Verify that Redis is running with redis-cli. If Redis is running, it will return: PONG:
    redis-cli ping
  2. Verify by using LiteSpeed default PHP info page http://Server_IP:8088/phpinfo.php. Look for the Redis Support section.

Try the redis-benchmark utility

A typical example would be:

redis-benchmark -q -n 100000
PING_INLINE: 31826.86 requests per second
PING_BULK: 31595.58 requests per second
SET: 33568.31 requests per second
GET: 31908.10 requests per second
INCR: 32647.73 requests per second
LPUSH: 31220.73 requests per second
RPUSH: 31565.66 requests per second
LPOP: 31555.70 requests per second

If you want to run one million SET operations, using a random key for every operation out of 100k possible keys, you can use the following command line:

redis-cli flushall 
redis-benchmark -t set -r 100000 -n 1000000


====== SET ======
  1000000 requests completed in 32.43 seconds
  50 parallel clients
  3 bytes payload
  keep alive: 1
99.98% <= 10 milliseconds
99.99% <= 11 milliseconds
99.99% <= 12 milliseconds
100.00% <= 17 milliseconds
30833.75 requests per second


For more redis benchmark information, please refer to this.

Integrate WordPress with Redis

See above

Other Settings

  • If you want to set up Master-Slave Replication, you may need to enable the firewall for port 6379:
    firewall-cmd --permanent --zone=public --add-port=6379/tcp
    firewall-cmd --reload
  • To automatically start Redis on boot:
    systemctl enable redis
  • For disk persistence, you can set /etc/redis.conf:
    • appendonly yes
    • appendfsync everysec
  • For more Redis Security information please refer to this

Using Memcached in a UNIX socket

Memcached can run in a UNIX socket, which provides better performance than a TCP connection.


If Memcached fails to start, it is usually due to permission and user problems. Please use root privilege to execute the following instructions, and verify that the socket path is writable to the designated user.


  1. Stop Memcached systemctl stop memcached
  2. Copy the service file cp /usr/lib/systemd/system/memcached.service /etc/systemd/system/memcached.service
  3. Add the following content to /etc/systemd/system/memcached.service. After [Service], please change username to the same user that runs PHP: User=username Group=username The contents of the file should look like this:
  4. Edit /etc/sysconfig/memcached, changing the path to your desired location, and the username to the same one used in Step 3: OPTIONS="" USER="memcached" becomes OPTIONS="-s /path/to/memcached.sock -a 0770" USER="username"
  5. Start Memcached again: systemctl start memcached
  6. Verify it started successfully: systemctl status memcached
  7. Check if everything is working well: nc -U /path/to/memcached.sock stats
  8. If there is still a permission issue, please check selinux status: getenforce
  9. Disable selinux if status shows Enforcing: setenforce 0 (reboot will re-enable selinux)
  10. To permanently disable selinux, edit /etc/selinux/config, change enforcing to permissiveordisabled and then reboot.


  1. Stop Memcached systemctl stop memcached
  2. Edit /etc/sysconfig/memcached and change OPTIONS="" USER="" to OPTIONS="-s /path/to/memcached.sock -a 0770" USER="username" where USER is the same user that runs PHP.
  3. Start Memcached service memcached start
  4. Check if everything is working well: nc -U /path/to/memcached.sock stats
  5. If there is still a permission issue, please check selinux status: getenforce
  6. Disable selinux if status shows Enforcing: setenforce 0 (reboot will re-enable selinux)
  7. To permanently disable selinux, edit /etc/selinux/config, change enforcing to permissiveordisabled and then reboot.

Ubuntu 17.10, Ubuntu 16.04, Debian 8 and Debian 9

  1. Stop Memcached systemctl stop memcached
  2. Edit /etc/memcached.conf, comment out host and port, add socket path and permission -s /path/to/memcached.sock -a 0770 and change -u memcache to -u username where username is the same user that runs PHP.
  3. Start Memcached again systemctl start memcached
  4. Check if everything is working well: nc -U /path/to/memcached.sock stats

Ubuntu 14.04 and Debian 7

  1. Stop Memcached service memcached stop
  2. Edit /etc/memcached.conf, comment out host and port, add socket path and permission -s /path/to/memcached.sock -a 0770 and change -u memcache to -u username where username is the same user that runs PHP.
  3. Start Memcached again service memcached start
  4. Check if everything is working well: nc -U /path/to/memcached.sock stats

Using Redis in a UNIX Socket

Please use root privilege to execute the following instructions. If Redis fails to start, please verify SELinux is disabled , and all mentioned directories and files have correct permissions to the designated user.

Centos 7.X

  1. Stop Redis. systemctl stop redis
  2. Copy the service file. cp /usr/lib/systemd/system/redis.service /etc/systemd/system/redis.service
  3. Edit /etc/systemd/system/redis.service. User=username Group=username Change username to same user that runs PHP.
  4. Edit /etc/redis.conf and change the following (Change port to 0 if TCP socket is no longer needed):
        unixsocket /path/to/redis.sock
        unixsocketperm 770
        logfile /path/to/redis.log
        dir /path/to/redis
  5. Change owner of redis.conf to same username in step 3. chown username:group /etc/redis.conf If /path/to/redis directory does not exist, please manually create it, and make sure above mentioned socket path, log pathand dir path and are writable by the designated user.
  6. Start Redis. systemctl start redis
  7. Verify it started successfully. systemctl status redis
  8. Check whether everything is working well. nc -U /path/to/redis.sock info

Last update: July 18, 2024