The default version of PHP available on Server running CentOS 7 is version 5.4. You will need to perform the upgrade by hand, since PHP 7 is not available in the standard CentOS 7 yum repository, because it is not considered stable.
This is a significant upgrade, with potential for causing serious conflicts with any web software you may be running.
We strongly recommend that you create a snapshot of your server before you proceed. This will allow you to roll back any changes if you encounter a problem with the upgrade.
php -v command to verify your current PHP version:
Upgrade to PHP 7
We will be using the IUS repository to upgrade PHP. Although there are several repositories which have made available versions of PHP 7 for CentOS 7, IUS is the only one which carries the official recommendation of the CentOS Project.
yum install https://centos7.iuscommunity.org/ius-release.rpm
Remove the existing version of PHP: yum remove php-common mod_php php-cli
Update packages: yum update
Install PHP 7: yum install php70u php70u-pdo php70u-mysqlnd php70u-opcache php70u-xml php70u-gd php70u-devel php70u-mysql
Restart Apache: systemctl restart httpd
php -v command to verify that PHP has been upgraded:
#php -v PHP 7.0.18 (cli) (built: Apr 13 2017 15:18:10) ( NTS ) Copyright (c) 1997-2017 The PHP Group Zend Engine v3.0.0, Copyright (c) 1998-2017 Zend Technologies with Zend OPcache v7.0.18, Copyright (c) 1999-2017, by Zend Technologies
These are the procedures to upgrade the php version.