How to install PHP 5.5 on CentOS 6 / 5

Epel & Remi Dependency for CentOS 6

rpm -Uvh http://download.fedoraproject.org/pub/epel/6/i386/epel-release-6-8.noarch.rpm
rpm -Uvh http://rpms.famillecollet.com/enterprise/remi-release-6.rpm

Epel & Remi Dependency for CentOS 5

rpm -Uvh http://dl.fedoraproject.org/pub/epel/5/i386/epel-release-5-4.noarch.rpm
rpm -Uvh http://rpms.famillecollet.com/enterprise/remi-release-5.rpm

For both (CentOS 5 and 6):

#Install the PHP core

yum --enablerepo=remi,remi-php55 install php php-common

Install additional common modules:

yum --enablerepo=remi,remi-php55 install php-cli php-gd php-pear php-mysqlnd php-pdo php-pgsql php-pecl-mongo php-sqlite php-pecl-memcached php-pecl-memcache php-mbstring php-xml php-soap php-mcrypt php-fpm

#Restart your web server to apply the changes:

service nginx restart​