How to integrate Redis with WordPress on LSWS

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.

For cPanel/Plesk/DirectAdmin and Native LSWS setup on CentOS 7:

1. Add the EPEL repository:
   

   yum install epel-release 

2. Install Redis:
   

   yum install redis

3. Start Redis:
   

   systemctl start redis

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

1. Installing the Redis PHP extension for all available versions of PHP (Copy and paste the entire block of text together - don't copy/paste line-by-line):

   for phpver in $(ls -1 /opt/cpanel/ |grep ea-php | sed 's/ea-php//g') ; do
   cd ~
   wget -O redis.tgz https://pecl.php.net/get/redis
   tar -xvf redis.tgz
   cd ~/redis* || exit
   /opt/cpanel/ea-php"$phpver"/root/usr/bin/phpize
   ./configure --with-php-config=/opt/cpanel/ea-php"$phpver"/root/usr/bin/php-config
   make && make install
   echo 'extension=redis.so' > /opt/cpanel/ea-php"$phpver"/root/etc/php.d/redis.ini
   rm -rf ~/redis*
   done
   
   /scripts/restartsrv_httpd
   /scripts/restartsrv_apache_php_fpm

2. Check Redis:
   

   for phpver in $(ls -1 /opt/cpanel/ |grep php | sed 's/ea-php//g') ; do
   echo "PHP $phpver" ; /opt/cpanel/ea-php$phpver/root/usr/bin/php -i |grep "Redis Support"
   done

   Output should be:

   PHP 55
   Redis Support => enabled
   PHP 56
   Redis Support => enabled
   PHP 70
   Redis Support => enabled 
   PHP 71
   Redis Support => enabled 

Note:

• You can check for the newest PHP redis version here
• To learn more please follow phpredis at Git

General Plesk support php-redis extention

If your Plesk version not support php-redis by default, please try compile Here

1. Add the litespeed repository:
   

   rpm -ivh http://rpms.litespeedtech.com/centos/litespeed-repo-1.1-1.el7.noarch.rpm

2. List the litespeed Redis PHP extension
   

   yum list | awk '/lsphp/&&/redis/'

3. Install PHP (substitute the your lsphp version if it is different):
   

   yum -y install lsphp71-pecl-redis

1. Verify that Redis is running with redis-cli:
   

   redis-cli ping

   
   If Redis is running, it will return:

   PONG

2. Verify by using LiteSpeed default PHP info page http://Server_IP:8088/phpinfo.php:
   

1. A typical example would be:
   

    redis-benchmark -q -n 100000 

   Output:

   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
   

2. 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

   Output:

   ====== 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

Note: For more redis benchmark information, please refer to this

1. Install the Redis Object Cache WordPress Plugin
   
2. Activate the plugin and click Enable Object Cache button
   
3. Confirm Status is Connected
   
4. Confirm Diagnostics shows Redis with version
   
5. Edit wp-config.php and at the end of the Authentication Unique Keys and Salts section, add the following lines:
   • define('WP_CACHE_KEY_SALT', 'string');
   • define('WP_CACHE', true);
6. Restart LSWS
   

   service lsws restart

7. Test that WordPress is communicating with Redis via a monitor command:
   

    redis-cli monitor 

   

• If you want to setup Master-Slave Replication, you may need to enable 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