当前环境：CentOS 7.6（x64）
卸载旧版本
rpm -qa | grep php
yum -y remove php-5.4.6
添加源
# epel源
yum list installed | grep epel
yum install epel-release yum-utils
# remi源
yum list installed | grep remi
yum install http://rpms.remirepo.net/enterprise/remi-release-7.rpm
使用remi-php73源
yum-config-manager --enable remi-php73
安装php7.3
yum install php php-common php-opcache php-cli php-gd php-curl php-pgsql php-zip php-devel php-gd php-mcrypt php-mbstring php-xml php-pear php-bcmath php-json php-intl php-phalcon4
安装PHP-FPM
yum install php-fpm
systemctl enable php-fpm
systemctl start php-fpm