1.安装源

 yum install epel-release
 yum install http://rpms.remirepo.net/enterprise/remi-release-7.rpm

2.安装yum管理工具

 yum install yum-utils

3. 查看php

 yum search php73
 yum search php74

4.安装php

 yum install php74-php-gd  php74-php-pdo php74-php-mbstring php74-php-cli php74-php-fpm php74-php-mysqlnd

5. 启动

service php74-php-fpm start