cd /usr/local/directadmin/scripts/custom
wget https://raw.githubusercontent.com/poralix/directadmin-utils/master/php/php-extension.sh -O php-extension.sh
chmod 750 php-extension.sh
./php-extension.sh
./php-extension.sh status redis

 redis-cli flushall

Edit Mysql 5.5
cd /usr/local/directadmin/custombuild/option.config

cd /usr/local/directadmin/custombuild
./build set redis yes
./build redis
./build set_php redis yes
./build php_redis