1. Install Atomic Repository On a CentOS Server:
wget -q -O - http://www.atomicorp.com/installers/atomic.sh | sh
The above command will download the atomic.sh script and then execute it. First the script installs the Atomic GPG key. Unless you have a Plesk server that you want packages for you can answer “n” when asked if you want to enable the Plesk yum repository. After this it will install the atomic.repo file in /etc/yum.repos.d/ directory.
2. Install php-zend-optimizer
By default only the atmoic yum repository is installed however you can also enable the atomic-testing repository and atomic-bleeding repository. Once installed issued the below command to install php-zend-optimizer.
yum install php-zend-optimizer
Now that Zend Optimizer is installed you can run PHP applications protected by Zend Guard. The Zend Optimizer package is now easily managed with the yum package manager.